Fehr was born on November 23, 1970, in Tel Aviv, Israel, the son of Gila (née Lachman), a day care supervisor, and Uri Fehr, a geophysicist. His parents' families are Jewish, and had come to Israel from Germany and the Netherlands. He trained at the Bristol Old Vic Theatre School in England after taking a very brief drama class in Frankfurt, Germany. He served in the Israeli army from 1989 to 1992 and used to work for security for the Israeli airline El Al in Germany.
Director Stephen Sommers cast Fehr in the films The Mummy and The Mummy Returns. Fehr's screen appearances have included the 2001–02 NBC series UC: Undercover, the 2002–03 CBS series Presidio Med, and the 2004 movie release Resident Evil: Apocalypse (he reprised the role in the sequel, Resident Evil: Extinction). He provided the voice of Doctor Fate in Justice League Unlimited, and played Antoine Laconte, a male prostitute, in Rob Schneider's comedies Deuce Bigalow: Male Gigolo (1999) and Deuce Bigalow: European Gigolo (2005).
He also acted in the American hit supernatural series Charmed, where he played the evil demon Zankou, the chief villain in that series' seventh season. Between 2005–2006 Fehr played Farik on the Showtime series Sleeper Cell. In 2013, he guest starred in the episode "Shiva" of the 10th season of CBS NCIS as an Israeli Mossad assistant director. Fehr returned to the fifth installment of the Resident Evil series, Resident Evil: Retribution.
Fehr married Rhonda Tollefson, whom he met at a Los Angeles opera, on December 22, 2000. The couple have two children: son Atticus (born January 4, 2003) and daughter Finley (born February 26, 2006). Fehr speaks Hebrew, English, and some German.
Gallery of behind the scene stills released to promote the actor.