When she became pregnant with Lucien, Lucien's mother was already married to Beron, the High Lord of the Autumn Court. Fearing for her life and the life of her unborn, as Beron's temper and penchant for violence were well-known to all, the Lady of Autumn attempted to pass her bastard son off as the true son of Beron. Her husband, however, had guessed the truth. For reasons unknown, however, he chose to accept Lucien as his blooded son (it is implied that this was done not for love of the Lady of Autumn Court or for Lucien, but to keep the truth of his wife's infidelity from being known to others, so Beron could save face and not be laughed at as a cuckold by others). Lucien, however, was never told the truth, and so believes himself to be the youngest blooded son (of seven sons) of Beron.
Lucien grew up in the Autumn Court, but never cared much about his nobility. He made friends with individuals of different courts and with individuals from non-aristocratic backgrounds. As Lucien was unlikely to become High Lord given that he was seventh in line for succession, he was allowed to roam the Court as he saw fit.
During his youth, he met a Lesser Faerie named Jesminda, who lived in the countryside in the Autumn Court. She teased and seduced Lucien until they eventually fell in love.  Beron disapproved of this relationship, however, as he believed it was inappropriate for a High Fae noble to marry a Lesser Faerie, and so he had Jesminda executed in front of Lucien. Two of his elder brothers restrained him during the sentencing and forced him to watch (neither of the brothers was Eris, Lucien's eldest and most sadistic brother, according to novel canon). 
After this, Lucien left the the Autumn Court and fled to the Spring Court, to Tamlin, the son of the High Lord of the Spring Court, whom he had befriended. His brothers believed that he was a contender to the High Lord's crown, and so three of them went to kill him, to prevent him from one day becoming High Lord. Lucien killed one of the brothers, while Tamlin killed the other. The third escaped back to the Autumn Court to report what had happened.
Now without a place at the Autumn Court, Tamlin gave asylum to Lucien and then appointed him to the position of Spring Court Emissary to all other Courts to give his friend some political protection through a title as well. After the appointment, the Autumn Court members dared not openly attack Lucien for fear of stating a war with the Spring Court.
As the emissary for Spring, Lucien met with individuals from other courts, including eventually his father, Beron, who he was forced to meet for political matters between the two Courts. Another such required meeting was with Amarantha, Hybern's former General and a witch of incredible power. Amarantha desired Tamlin and wanted a relationship with him, but Tamlin was not interested. To convey his disinterest in a politic manner, but to discuss how they might keep the peace despite it, Tamlin sent his emissary, Lucien, to her to parlay. Amarantha did not take Tamlin's rejection well, however, and she allowed her anger to get the better of her, claiming there would be no peace so long as Tamlin refused her. In a rare moment of losing his temper, Lucien told Amarantha to, 'go back to the shit-hole she'd crawled out of'.  As punishment for his words, Amaranatha attacked Lucien and carved out his left eye. She sent him back to the Spring Court severely wounded to serve as both a grave insult and as a challenge to the Spring Court for war.
Lucien's face was left scarred from the incident. Nuan, an alchemist from the Dawn Court, aided the Spring Court in Lucien's healing, however. She crafted a metal eye and gave it to Lucien to use as a replacement for his left eye. 
Not long after those failed 'negotiations', Amarantha hosted a ball Under the Mountain and claimed it was to make amends for removing Lucien's eye. The entire Spring Court attended, including Lucien, who wore a fox mien for a mask. Amarantha claimed the ball would be a masquerade, so Lucien could hide the scarring. Her true motive for the party was to seduce Tamlin into becoming her lover and consort. However, Tamlin was outraged at the injuries that Amarantha had inflicted upon Lucien and so he refused her again. To add insult to injury, he told the witch he would rather take a Human to bed than her. Facing his scorn before a room full of Fae humiliated Amarantha, and so she cursed the entire Spring Court, which now included Lucien, to forever wear their masks. The only chance to break this curse was for Tamlin to fall in love with a Moral Human girl who despises faeries, and he was given a time limit of "seven times seven years" (49 years total) to break the curse. If he did not manage to complete this task in time, Amarantha would claim him and all of his subjects as slaves and imprison them in Under the Mountain forever.
To aid his best friend and end the curse on all of them, Lucien vowed to help Tamlin try to find this Mortal Human female of Amarantha's prophecy.
A COURT OF THORNS AND ROSES
During the 49th and final year of the curse, a Mortal Human female named Feyre Archeron kills one of the Spring Court's male Fae who has been sent over the wall to search for the girl of Amarantha's prophecy.
Lucien, along with Tamlin, believes Feyre is the one they've all been waiting for.
Tamlin brings her under duress (by threatening her family) to the Spring Court. At first, Tamlin is somewhat cold and distant from his prisoner-slash-intended savior, and so Feyre turns to a kind face within the Spring Court for friendship, Lucian. The two build a good rapport, and Lucien even encourages Feyre's relationship with Tamlin. The two often go hunting together and it is Lucien who first instructs Feyre as to how to ensnare the Suriel for aid.
After the events of Under the Mountain, when Amarantha torments Feyre with her challenges, Lucien remaines steadfast and loyal to his best friend, Tamlin, and to the course of removing the curse, even as he worries for Feyre's health and safety.
After Amarantha is killed and the curse is lifted, Feyre is re-Made a Fae. She returns to the Spring Court with Tamlin, believing herself in love with him. Lucien accompanies them and makes the Spring Court his permanent home.
A COURT OF MIST AND FURY
In "A Court of Mist and Fury", Tamlin's irrational need to suddenly control Feyre's every move is seen by Lucien, and as such he does what he can to alleviate some of that control, often at the expense of his own well-being. From providing her with weapons to hide on her person when Tamlin wouldn't, to begging Tamlin to allow them to properly train Feyre to use her newfound powers, Lucien was seemingly the only memeber of Spring to fight for autonomy. When Tamlin locked her in the mansion, Lucien urged her to be patient, promising to see what he could do in order to set her free, despite the recents threats on his life.
After Feyre disappears during the middle of her wedding ceremony to Tamlin, Tamlin sends Lucien out into Prythian to find and bring his intended bride back to him. Lucien spends weeks searching for her, and eventually corners her in the wilds of the Night Court, while she is out training up her new skills with Azriel. Lucien believes Rhysand and the Night Court have bewitched Feyre somehow and that she is not in her right mind when she makes it clear to them that she is not going back to Tamlin. She utilizes her new powers to frighten Lucien and threatens Lucien into leaving. He returns to Tamlin with Feyre's message and news of her new abilities.
Knowing he does not have the power alone to go up against Rhysand, whom he believes has manipulated Feyre with magic into staying with him, Tamlin throws his lot in with the King of Hybern, who has plans to conquer and take over Prythian. Lucien goes with him into the lion's den, loyal to Tamlin's cause.
When Feyre, Rhysand, Azriel, Morrigan, and Cassian infiltrate Hybern's castle on the Island of Hybern, they are captured by the alliance of Hybern's King, Jurian, Tamlin, and Lucien. As Hybern torments them, he brings out a secret weapon against Feyre: in the 'spirit' of the alliance Tamlin has brokered between the Spring Court and Hybern, the priestess, Ianthe (who has latched onto the Spring Court through Tamlin's naivety), has turned over to him Feyre's sister, Nesta Archeron on Elain Archeron as prisoners of war. As Tamlin shows disapproval of this move, Lucien's attention becomes fixed on Elain.
When Hybern's King orders Elain thrown into the Cauldron, to discover the truth as to whether it will reMake her as it did Feyre, Lucien becomes upset. He demands Hybern to stop, but Elain is tossed into the black waters of the Cauldron anyway. When she emerges moments later, she has been re-made into a High Fae like her sister. Lucien feels the mating bond snap into place between him and Elain and tells her such immediately.
He goes to Elain's side while Hybern's King then decides to test the Cauldron on the second sister, Nesta. When she, too, is reMade into a Fae by the Cauldron, it becomes clear to Feyre that Hybern's King will continue their torment, either though he has the answers he sought. While Feyre fakes breaking free of Rhysand's 'mind manipulations' (a ruse to make the enemy believe they were right all along), Lucien gathers Elain up and helps her to her feet. Feyre negotiates with Hybern's King to allow Rhys, Cassian, Azriel, and Morrigan to escape by feigning the effects of breaking Rhysand's 'spell' upon her, begging him to let it end so she can return to Tamlin and find some peace. In the confusion, Feyre has broken through the magical wards around the castle, giving her friends an opportunity to get out. The Morrigan moves first, Winnowing to Elain and Nesta and taking them from Lucien's care, while Rhys gathers Azriel and Cassian. The six escape Hybern's castle for the Night Court. Lucien is bereft at the loss of the mate he's just discovered, and demands Tamlin go after them. Feyre inserts herself, however, as a tired victim of Rhysand's manipulations and asks Tamlin to simply take her home, knowing the High Lord of Spring will grant her wish before his best friend's.
In this way, Feyre has sown the first sliver of discord between Lucien and Tamlin's long-time friendship.
A COURT OF WINGS AND RUIN
In "A Court of Wings and Ruin", Lucien is forced to babysit Feyre at the Spring Court for Tamlin. He remains at his friend's side for this purpose, despite his resentment of that fact. His instinct, however, is to find Elain Archeron and get to know her, and that need remains a constant unmet demand upon him.
As the weeks go by, he begins to seriously doubt Feyre's story about having been Rhysand's prisoner and how her imprisonment by him emotionally and mentally took a negative toll upon her. Lucien does not trust her any longer and suspects she has a much more manipulative game in play than anyone sees, especially Tamlin. The friendship he and Feyre had once shared is now tarnished by too many lies and deceit.
A few weeks after the events in Hybern's throne room, Prince Dagdan and Princess Brannagh are sent to the Spring Court by Hybern's King, their uncle. From the beginning, it is clear Lucien does not like either 'guest', but as he is assigned to watch Feyre by Tamlin, that means he is to go with her everywhere. When Feyre escorts the Prince and Princess to the Wall, so they can inspect it for weaknesses, Lucien accompanies them. During that first journey, Lucien aids the twins by supplying information regarding the holes in the Wall, albeit reluctantly.
While they are away from the castle and Tamlin on that same extended trip, Lucien confronts Feyre with his suspicions, and Feyre confides in him about what happened during her absence from the Spring Court (Feyre is quiet about the truth of her relationship with Rhys, however).  The friendship that was once there between Lucien and Feyre is tentatively rebuilt, although it is clear on both sides that there is still great mistrust.
They all return to the castle soon after.
A few days later, the Summer Solstice arrives. Like all of the Spring Court, Lucien attended these celebrations, though he is half-asleep during one of Ianthe's performances. During one particular performance, however, Ianthe is interrupted by Feyre who uses the power she acquired from the High Lord of the Dawn Court when she was reMade to glow, creating a display of light that makes her appear 'holy' and 'blessed' by the Mother (more so than Ianthe). Lucien wakes up, awed by the display. He moves to her side and takes her hand, kneeling on the floor at her feet, adding to the dramatics of the spectacle.  The incident creates jealousy in Ianthe, who expected to be the center of attention that day, and in Tamlin, who does not like the look of adoration for Feyre showing in Lucien's eyes (he sees it as more than 'friendly' interest in her). After the celebration, Lucien escorts Feyre back to her room, too, causing Tamlin's 'green-eyed monster' to gnash its teeth in frustration.
In that one act, Feyre sends Ianthe into a panic (forcing her to do something even more rash to secure the attention of everyone else to restore her place of importance in the Spring Court) and continues to sow discord between Lucien and Tamlin.
That same night, after the celebrations have ended, Lucien's sleep is interrupted by Feyre's screaming. He is used to hearing her cries at night due to her nightmares, and so tries to go back to sleep. She knocks on his door, however, and he opens the door to his chambers shirtless...to find her wearing sexy, lacy clothing and in disarray from her night terrors. She tells him she has terrible dreams of her time Under the Mountain, and hugs Lucien for comfort. Their somewhat sensual embrace is interrupted by Tamlin, who becomes angered at the scene of his best friend and his lover in so intimate contact. Feyre quickly leads Tamlin out of Lucien's room to avoid Tamlin from killing his best friend, knowing Tamlin's temper.  Lucien knows then to keep a distance from Feyre or risk Tamlin's irrational violence.
The next day, Feyre and Lucien again escort Dagdan and Brannagh to the Wall, however this time they visit the Continent as well to inspect its Wall. Brannagh is unable to winnow, and Dagdan can only winnow a few miles, and so the group winnow and hike to the continent. During their trek, three members of the Children of the Blessed approach them. Lucien rejected their plead to dwell in Prythian, though Brannagh and Dagdan are enticed by their offer. The next day, Lucien finds the three Children of the Blessed dead and their bodies mutilated by Brannagh and Dagdan.  As retribution, Lucien and Feyre sent the Bogge after the Hybern twins, though they escape unharmed. For this trickery, both Lucien and Feyre are scolded by Tamlin. Feyre, however, turns the scolding around on Tamlin, causing his anger to unleash his magic. She purposely does not shield herself and is injured by furniture being thrown around the room by Tamlin's wild magic. In the shocking silence after, Lucien immediately runs to Feyre's aid to get her out of the room, and this only further needles Tamlin's jealousy.
A few days later, as a result of a plot Feyre secretly concocts to ruin Ianthe and to stir up anger in the Spring Court's citizens and its soldiers, Tamlin is forced to publicly whip one of his sentries. During the sentencing of this soldier, Lucien holds Feyre's hand to support her.
The scheme succeeds, causing the people of the Spring Court to rethink their loyalty to their High Lord - and forcing Lucien to finally admit that his best friend, Tamlin, has lost all good reason and has become a tyrant on the wrong side of a coming war.
During the last visit out to the Wall, Lucien once again accompanies Feyre, Dagdan and Brannagh. However, this time, Ianthe and Tamlin also attend them (Tamlin out of jealousy, Ianthe seeking opportunities to insert herself in any way possible into power). When Lucien is left alone with Ianthe at one point during the trip, she tricks him and ties him in shackles to force him to accept her unwanted sexual advances. He coldly rejects her, and is saved by Feyre who uses her Daemati abilities to force Ianthe to unshackle him.  After, Brannagh and Dagdan appear and confront Lucien and Feyre, admitting they've been using small amounts of Faebane to poison her and Lucien for weeks. Lucien and Feyre team up to fight and eventually kill the Hybern twins.
Murdering the niece and nephew of the Spring Court's ally, Hybern, severs any chance for Feyre and Lucien to return to the Spring Court, however. They know their lives will be forfeit now, and flee from the Spring Court, running into the Autumn Court on their journey north towards the Night Court, knowing it is their only chance for safety.  Weakened by the Faebane, though, the two wary companions are forced to travel on foot. They trek through the Autumn Court, and through the Forest House, a passage which takes days. Eventually, near the border between the Autumn and Winter Courts, they are intercepted by Lucien's brothers, one of whom is Eris. They fight against the brothers and barely manage to escape. They settle in a cave for the night, and pass the time talking. Feyre tells Lucien about her sister, Elain.
The next day, they enter the Winter Court, but are again intercepted by Lucien's brothers. Fortunate timing brings Azriel and Cassian to their aid. Frightening off Lucien's brothers, the two Illyrians fly the weakened Lucien and Feyre together back to Velaris.
Though wary of the Night Court, Lucien is amazed at the peace in Velaris and comments on how there are children laughing in the street in surprise.
When they reach the home where Elain and the others are rehabilitating at long last, Elain appears to have not recovered well from her kidnapping and forced reMaking by the Cauldron. She drifts from place to place, seemingly uncaring about where she's at or even eating, and she speaks in odd, disjointed sentences sometimes (these nonsense phrases actually turn out to be prophetic visions of the future, as she's been Made into a Seer by the Cauldron's magic). Worse, Elain refuses to acknowledge Lucien, pining away for her Mortal male fiance, Graysen.
Eventually, Lucien realizes that Elain will not acknowledge the mating bond between them so long as she is mourning her lost Human love. Time and distance is all that will heal her and give them a chance, so he agrees to help Feyre and the Night Court in gathering allies for the coming war with Hybern. He leaves Velaris and ventures out into the world to find the missing Mortal Queen, Vassa, in an attempt to win her aid in the coming war. Where he specifically goes is unknown.
Eventually, Lucien reappears at the final battle between Hybern and Prythian. He is accompanied by Elain's father and his Mortal army, as well as Vassa, the Seraphim army under Prince Drakon and Miryam, and Tamlin and his Spring Court (who have betrayed Hybern to come to the aid of the rest of Prythian). Together with the forces of Night, Day, Dawn, Summer, Autumn, and Winter, and with the powers of the Bone Carver, the Weaver, Bryaxis, and Amren revealed and unleashed, the combined armies conquer Hybern's forces.
In the aftermath of the war, Lucien watches Elain from a distance, recognizing that she has been jilted and heartbroken by Grayson, who cannot abide her new Fae form (for his prejudice against Fae is too deeply entrenched for him to look past it). He knows he may never win Elain's acceptance, much less her heart, and so he leaves her to travel with Vassa and Jurien, who both survived the war as well.
A COURT OF FROST AND STARLIGHT
It has been months since the end of the war and Lucien has been traveling the world at the side of his two new companions, Jurian and Vassa, who is cursed by the sorcerer, Koschei, to turn into a fire bird every day when the sun rises (only to revert to human during the night hours). The triad's relationship seems to imply more than just friendship, and Lucien seems happy and more content than he's been in a long time.
Lucien's skin is tanned, noticeably darker than his half-brothers. He has red (crimson) hair. His face is brutally scarred from his brow to his jaw, a wound inflicted by Amarantha. His right eye is whole and russet colored; the left eye was ripped out by Amarantha and has been replaced with an artificial mechanical eye made of gold (created by a talented female alchemist from the Day Court). His features are described as sharp, elegant, and ethereally handsome despite the length of scars on his face.
Lucien is sarcastic and witty, but kind and loyal to a fault. He is a male with many emotional scars as a result of Beron's cruelty and abuse of him, which emboldened his elder brothers to all treat him similarly. His mother is devoted to him, and he is the only one of her sons she truly loves (perhaps because he was conceived in love with Helion, the Lady of Autumn's true mate). Lucien covers up his anguish under the guise of a bright, charismatic personality. He deeply cares for people, and is shown to be affected by things more on the inside than he lets it show on the outside.
While living in the Autumn Court, Lucien met Jesminda, a Lesser Faerie who lived in the countryside. She teased and seduced him until the pair eventually fell in love. Jesminda appreciated Lucien for who he was, instead of loving him for his noble rank. Lucien loved her with the same amount of appreciation, and even believed she was the most beautiful female he knew. The pair were not mated, though this did not diminish their love.
The pair's love was cut short, as Beron believed it was inappropriate for a High Fae noble to have a relationship with a Lesser Faerie, and so he executed Jesminda in front of Lucien. This had a harrowing effect on Lucien, who fled to the Spring Court for safety.
Lucien is bitter and cold towards Ianthe, rejecting her sexual advances. Ianthe, however, is interested in the prospect of having a child with Lucien, as their offspring would be powerful and respected. She attempts to gain his interest, but he consistently ignores her. During the night of Calanmai, Tamlin refuses to participate in the Rite, and so Lucien believes it is his duty to perform in the rite, and so sleeps with Ianthe. This night is something Lucien regrets and is deeply embarrassed about. After Ianthe kidnaps Elain and takes her to Hybern, Lucien becomes more bitter to Ianthe. He shows her no gratitude for what she has done. Despite the constant rejections, Ianthe locks him in shackles thus forcing him to accept her sexually. Lucien does not concede to her advances even after this. He is saved by Feyre, and leaves Ianthe in the Spring Court.
- The name Lucien is French and means 'light'.  Ironically, in A Court of Wings and Ruin, Lucien is revealed to be the biological son of Helion, the High Lord of the Day Court. Helion has the power to manipulate light.
- Sarah J. Maas originally planned for Lucien to have a romantic relationship with Nesta. However when she started writing A Court of Mist and Fury, Maas came to the conclusion that this relationship wouldn't work. 
Notes and references
- A Court of Thorns and Roses (First appearance)
- A Court of Mist and Fury
- A Court of Wings and Ruin
- A Court of Frost and Starlight
|Characters||Rhysand · Feyre Archeron · Amren · Morrigan · Cassian · Azriel · Nesta Archeron · Elain Archeron · Lucien Vanserra · Nuala · Cerridwen · Keir · Devlon · Clotho · Madja · Bryaxis · Sevenda · Rita · Thanatos · Thanatos's daughter · Rhysand's father † · Rhysand's mother † · Rhysand's sister † · Enalius|
|Locations||Cesere · Hewn City · Palace of Bone and Salt · Palace of Thread and Jewels · Rainbow of Velaris · Restaurant · Rita's · Sidra River · The Prison · Velaris · Western Isles|
|Characters||Tamlin · Feyre Archeron (former) · Lucien Vanserra (former) · Alis (former) · Ianthe † · Andras † · Bron · Hart · Tamlin's father · Tamlin's mother · Ianthe's father · Ianthe's mother · Ianthe's sisters|
|Locations||Village · Western Forest|
|Characters||Beron Vanserra · Eris Vanserra · Lucien Spell-Cleaver (former) · Jesminda †|