Not a whole lot is known about Spike's history. He acquired the nickname "Spike" due to his penchant for torturing his victims with Railroad Spikes. He was known as "William the Bloody" when he was still mortal. As stated above, it is not entirely certain who sired him. Spike himself has stated on several different occasions that Angel/Angelus is his sire. Yet, it has been stated in numerous magazines and novels that Drusilla was his Sire. You decide.

Angelus, Spike and Drusilla were a close-knit family of sorts for several decades before Angelus regained his soul and left them alone. Once Angeluswasgone,Spike took it upon himself to take care of Drusilla.

Spike has killed two slayers in his time, but it is unknown when, how or even who they were.Spike and Drusilla came to Sunnydale in 1997, in an effort to cure Drusilla. She was weakened by a mob in Prague. Shortly after their arrival, Spike killed Colin, the Annointed one after a failed attempt to kill the Slayer on Parent-teacher night.

After their initial meeting, Spike's has had numerous close calls with the Slayer and her friends. All have ended badly. After kidnapping, and nearly killing Angel in an attempt to restore Drusilla's health, Spike was caught in a fire after an organ fell on him. Drusilla, who had regained her strength, pulled his body from the wreckage. He was wheelchair bond for several months.

Shortly after he was injured, Angel lost his soul again and rejoined Spike and Drusilla. Spike's elation at having Angelus back was short-lived, once he realized the lengths Angelus would go to to taunt him.

After several long months, Spike entered into a truce with the Slayer. He would help her kill Angelus, if she allowed him and Drusilla to leave Sunnydale, unharmed. In the fight that followed, Spike was forced to render Drusilla unconscious and carry her away, leaving Buffy to fend for herself against Angelus.

Drusilla couldn't forgive Spike for him helping the Slayer defeat her 'daddy', and left him. Spike returned to Sunnydale in November 1998, highly enebriated He kidnapped Willow and Xander, insisting that Willow perform a love spell to get Drusilla back. He left, without the spell, deciding instead to torture her until she loved him again.

 Spike returned to Sunnydale in October 1999, in search of the fabled Ring of Amarra, which was considered to be a sort of 'holy grail' for vampires. With it, nothing could harm him.

After losing it in a fight with the Slayer, Spike followed the ring to Los Angeles, where it was delivered into Angel's hands. He kidnapped him, and had him tortured in an effort to get the ring back. Neither worked. Angel ended up with the ring, which he destroyed. Spike left.

In November, 1999 Spike returned to Sunnydale, only to be captured by the Initiative, a secret, government organization whose soul purpose was to hunt and study vampire and other demons. While ion their custody, Spike was implanted with a 'behavior modification chip', which prevents him from harming humans in anyway. He can't even think violent thoughts with painful repercussions.

Spike escaped the Initiative labs, not knowing about the implant. Thinking The Slayer was behind the Initiative and his capture, Spike went to her dorm to kill her. However, he found Willow instead. After a failed attempt to kill or turn her, there was a small showdown between himself, the Slayer and some of the Initiative's commandos. He escaped.

Spike found himself unable to feed and kicked out of his lair, whom he had recently shared with Harmony. He went to Rupert Giles house. He offered to give them information on the Initiative in exchange for blood and shelter.

  After a botched spell, Spike was engaged to Buffy for a short period of time.

When he attempted to commit suicide, Spike was stopped by Willow and Xander, who took him with them to the demolished Sunnydale Highschool,where some demons were attempting to reopen the Hellmouth. It was at this time that Spike discovered that although he could no longer harm humans, demons were fair game. This new knowledge excited him. He had missed the violence of a good kill.

Spike moves out of Xander's basement and into his own crypt.

When Giles is turned into a demon at the hands of Ethan Rayne, it is Spike who helps him, for a price.

Spike is shot by a member of the initiative, imbedding a tracer in his skin. With the help of one of Willow's spells, Giles removes it.

Spike is approached by Adam, a frankenstein-like creation of the Initiatives. He wants Spike to spy on the Scooby gang for him. He will remove Spike's implant if he helps him. Eventually Spike is asked to separate the Slayer from her friends, which he does with pleasure. However their separation is short-lived, and in the end, Spike helps Willow, Xander & Giles by killing a demon before it can kill them. He does this in an effort to keep them from staking him on sight. It works.

Buffy finds out that Spike has a crush on her, what later turns out to be a huge obsession. Spike seems to become more and more a good guy, he helps Buffy fighting Glory, an evil Goddess. Buffy dies in that battle. When her friends bring her back to life with a spell, Spike helps her with her problems. Buffy uses Spike to have a lot of sex. Because she doesn't really love Spike she dumps him again. He is really upset about it and he even tries to rape Buffy. He feels so bad about what he did and is, that he goes to Africa to get his soul back.
In the 7th season Buffy finds out Spike lives in the basement of the new high school. He's a total mess and even talks to himself. Because of the first evil Spike gets to bite and kill people again. Buffy helps him with that. Spike gets back to normal again. When he's at her house tied up in the basement (So he won't hurt anyone) he gets kidnapped by the first and people who are working for it. They try to get him on their side, and torture him a lot. But he doesn't give in, he believes that Buffy will come and save him. And she does. The next problem is that Spikes chip is starting to work really strange, and he's in terrible pain. Buffy feels sorry for him and tries to help him with it. When she got the choice of removing the chip or get it fixt, she let's it get removed. Everybody (especially Gilles) thinks that Buffy has made a very stupid choice, but Buffy knows that his soul will stop him from hurting people, she believes in him. Gilles decides he want to do some tests with Spike. Because every time Spike hears an old song (Early One Morning) he turns into a monster, and tries to kill everyone. After they put something in his brain we see Spike when he was still a normal man, still William, living with his mother. She always used to sing this song for him. The song turns him crazy because he hates his mother. Not long after Drusilla sired him, William went back to his sick mother and decided to sire her. After he does so his mother makes a fool out of him and throws a lo of bad words at him. Spike gets angry and kills his mother with a stake.

Later we find out that the principal of the new high school, Wood, was the son of the Slayer that Spike killed in the Subway. Wood tries to take revenge for his mother and tries to kill Spike, but he fails. When all of Buffy's friends want her to leave the house Spike is the only one who is on her side. That night Spike tells Buffy how he really feels about her. And later that night they fall asleep in each others arms. Then Angel comes to town, he wants to help Buffy in the fight, but she refuses. After Spike sees them kiss he walks away, angry and sad. When Buffy comes home she gives Spike an Amulet that Angel gave her. Spike is still some kind of angry about Buffy's and Angels kiss but Buffy tells him it's nothing and they sleep together again. The next day they finally are going to fight against the first. Spikes amulet that he is wearing (the one Angel gave Buffy) starts to glow. It kills all of the vamps in the room; Spike is being pushed to wall. He is burning up from the inside. Buffy walks over to him and tells him to leave, but he says he wants to see this end. Buffy holds his hand, which is on fire. She tells him she loves him but he doesn't believe her. Buffy leaves. Then Spike dies. Rest in Peace, darling.

Spike joins in the last season of Angel, Angel has taken over Wolfram and Hart.  He has decided to fight them from the inside, and possibly use their resources to do good.  However, Wolfram and Hart have their own agenda, in an attempt to bring Angel onto their side.  In this final season, Spike has been brought into the group, at first as a ghost due to his end on Buffy.  Once  Spike becomes corporeal again, it causes trouble because now there are two vampire champions with a soul.  As the apocalypse gets closer, an Old One known as Illyria infects Fred and takes over her body.  With Fred's death, it has split the gang apart.  Wes tends to Illyria, realizing that Fred is gone forever, and he cannot bring her back.  As the mind wipe at last season's end is brought up, Connor is brought back into the picture as everyone prepares for one final battle against the Senior Partners, and Cordelia returns to give Angel her visions so that he can continue fighting the good fight.