By Simon Vozick-Levinson
Updated July 18, 2007 at 12:00 PM EDT

As regular PopWatchers are well aware, tracking the casting process over at NBC’s Law & Order can be every bit as suspenseful as actually watching an episode of the venerable cops ‘n’ courtrooms series. Last we heard, the departure of real-life presidential hopeful Fred Thompson (a.k.a. on-screen D.A. Arthur Branch) had left the top “Law” seat open, while the supremely talented Jeremy Sisto was replacing rookie cop Milena Govich on the “Order” side of things. Well, the producers revealed two more twists to the developing tale today — one pretty predictable, the other a complete surprise, and each in its own way quite satisfying.

Obvious things first: Sam Waterston’s A.D.A. Jack McCoy is indeed getting the well-earned promotion that rumor suggested was coming his way. In retrospect, he’s really the only candidate who made any sense for the vacant D.A. job. Sure, this means no more closing-argument fireworks or outraged “Objection!”s from McCoy, but mature reflection was more his style lately, anyway. Waterston’s character had served as a de facto elder statesman on the show for years now, and it’ll be nice to see him taking on that role full-time. (One stray thought: D.A. is an elected position in New York, so does this mean we might get to see McCoy hit the campaign trail this fall — at the very time when Fred Thompson’s non-fictional White House run starts going into high gear? How meta.)

But the really exciting news today is McCoy’s replacement in the A.D.A. slot. Turns out the new prosecutor will be played by none other than Linus Roache (pictured) — one of Sisto’s co-stars on Kidnapped, the fantastic thriller series that NBC callously canceled last fall. (NBC is currently burning off Kidnapped‘s final episodes,previously consigned to, on late Sunday nights; I can’trecommend highly enough that you sacrifice some Z’s to check ’em out.) In that show’s roster of world-class character actors, Roache played an FBI agent who cooperated uneasily with Sisto’s freelance badass on a high-stakes abduction case. Come to think of it, their relationship wasn’t all that different from the one you might find between an uptight A.D.A. and a gritty homicide detective. I’ve resigned myself to the fact that I’ll never get to see a second season of Kidnapped, but I’ll happily take this resurrection of sorts as a consolation prize.

addCredit(“Linus Roache: Djamilla Rosa Cochran/”)