AceShowbiz -

Alec Baldwin's role on "Law & Order: Special Victims Unit" has been revealed after his casting was confirmed earlier this month. In the episode directed by Mariska Hargitay, the "30 Rock" alum will play Jimmy MacArthur, "a controversial New York newspaper columnist who questions the SVU squad's motives during the investigation of a potential hate crime/rape case."

In the same outing, real-life journalist Katie Couric is set to make a cameo appearance. She will appear as a talk show host questioning MacArthur about the case.

"I'm thrilled to be directing," Hargitay says of her directing debut in the March 19 episode. "It's been a goal of mine for a long time, and it's quite an experience to see it realized. My respect for the process of making this show and telling these important stories deepens with every scene we shoot."

She adds, "I have always been so honored to work with this cast and crew, but never more so than now, as a director collaborating in a new way. And I've watched Alec on screen for so long and always hoped we would be able to work together some day. Having the opportunity to tell this story with him, having him bring his experience, depth, truthfulness, and fierce commitment, honestly feels too good to be true."

Showrunner and executive producer Warren Leight dishes on the plotline for the episode. "New York City has had a long history of high profile and controversial newspaper columnists, whose influence extends beyond the newsroom," he says.

"In our story, 'Jimmy Mac's' reporting interferes with the investigation, which has a ripple effect when the case goes to trial. We couldn't ask for a better actor for Mariska to work with in her directorial debut. Their chemistry on screen is palpable."

Titled "Criminal Stories", the episode will also feature The Roots' drummer Questlove as a victim.