James Wesley Marsters (born August 20, 1962 in Greenville, California) is an American actor and musician, best known for playing the popular platinum-blond character Spike, a vampire, in the television series Buffy the Vampire Slayer, its spinoff series Angel, and as Dr. Milton Fine (Brainiac) in the series Smallville.

He grew up with his brother and sister in Modesto. Dreaming about becoming an actor since he played Eeyore in Winnie the Pooh in fourth grade, James joined the theater group at his high school, acting in many plays, including musicals.

After graduation, Marsters studied at the Pacific Conservatory of the Performing Arts, 1980-1982, and Juilliard Drama School, 1982-1984.

Marsters moved to Chicago where his first professional acting role was Ferdinand in The Tempest at the Goodman Theatre in 1987. He also appeared with well known Chicago companies such as the Northlight and the Bailiwick and with his own group, the Genesis Theatre Company. Marsters was nominated for a Joseph Jefferson award for his performance of the lead role of Robespierre in the six hour drama Incorruptible: The Life, Death and Dreams of Maximilian de Robespierre in 1989.

In 1990, Marsters moved to Seattle and formed the New Mercury Theatre, named after Orson Welles' own theatre group. In this and other companies, Marsters was involved in a wide range of plays, including Teechers (a British play by John Godber), Anouilh's Antigone, an original work based on the Dr Seuss books, and Shaw's Misalliance.

In 1992, Marsters got his first acting job on TV — on Northern Exposure, a show that was shot near Seattle. He has made guest appearances on several popular television series such as Andromeda, as well as the independent films Chance, Winding Roads and the 2005 USA Network movie Cool Money. During November, 2005, Marsters filmed a thriller, "Shadow Puppets," with Jolene Blalock which is scheduled for release in March, 2006.

In 2003-2004, Marsters was also lead singer for the rock band Ghost of the Robot. Their debut album Mad Brilliant was released on February 2, 2003. The band played its first gigs in LA and Paris. They went on to play successful dates in and around LA and two sold-out tours of Europe in 2003 and 2004. They released one CD album, Mad Brilliant; three singles, Valerie, David Letterman and New Man; and one mid-length "EP", It's Nothing. All these releases carried tracks written and co-written by him.

Marsters' solo musical career was launched in October 2004, in London. His solo acoustic tour of the UK in April 2005 sold out and was a huge success. A new solo album Civilized Man was released on April 15th, 2005. It includes several new songs as well as the popular Katie and Smile. Ten of the eleven songs are written by Marsters.

Marsters has also narrated the audiobooks for The Dresden Files, a series of detective novels with a supernatural bent. The third audio in the series, Grave Peril was released in March of 2005.

In late 2005, Marsters appeared on the television series Smallville playing Dr. Milton Fine (a.k.a. supervillain Brainiac) in episodes 1-Arrival, 4-Aqua, 5-Thirst, 7-Splinter, and 8-Solitude.

On October 29, 2005, Marsters presented two performances of his own abridged adaptation of Shakespeare's "Macbeth" with American actress Cheryl Puente as Lady Macbeth, followed by question and answer sessions with the audience and acoustic concerts in London.

Marsters starred in a horror film, "Shadow Puppets," which is in post-production.

An interesting side note is that when asked where he got the inspiration for his English accent in Buffy The Vampire Slayer and Angel, Marsters said it was from his co-star, Anthony Stewart Head. Head, who was born in Camden Town affects a light, Received Pronunciation accent as Giles; he has a deeper, more notably London accent when not in character.