Linus Roache, who co-starred in "Kidnapped" last season, is staying with NBC and joining the cast of "Law & Order."

The British-born, Golden Globe-nominated Roache will play the show's new lead prosecutor, stepping into the well-worn shoes of Jack McCoy (Sam Waterston) when the show begins its 18th season in January. McCoy, in turn, has moved up to the more political role of district attorney for Manhattan, replacing the departed Arthur Branch (likely presidential candidate Fred Thompson, who has left the show).

"I've known Linus' work for several years," "L&O" executive producer Dick Wolf says. "He is an actor who totally gets inside his roles. I think he and Sam are going to raise the bar and add intellect and passion in the back half of the show."

Roache is the second member of the "Kidnapped" cast to move over to "Law & Order." Jeremy Sisto, who starred in the short-lived NBC series, is playing a new detective on the homicide squad partnered with Ed Green (Jesse L. Martin).

Roache also appeared in the pilot for FOX's midseason drama "Canterbury's Law"; there's no word yet on whether he'll work on both shows or if his "Canterbury's" part will be recast.

He earned a Golden Globe nomination in 2003 for the FX movie "RFK," in which he played the title role. His other TV credits include ABC's remake of "The Ten Commandments" and HBO's "The Gathering Storm." His movie roles include "Batman Begins," "The Namesake" and "The Forgotten."