By Lynette Rice
Updated March 28, 2013 at 09:34 PM EDT

William Petersen remains one of the more sought-after actors to headline a TV show but the former star of CSI isn’t ready to come back to broadcast TV … yet. Instead, he’s set to appear Friday opposite Julia Stiles in Blue, a web series in its second season from Rodrigo Garcia (Albert Nobbs, In Treatment) about a single mom who’s trying to protect her son from the consequences of her secret career as an upscale escort. Petersen, who splits his time between Los Angeles and Chicago, plays Blue’s (Stiles) father, who has been in jail for the majority of her life and is serving a life sentence.

“Rodrigo just asked,” Petersen tells EW of the one-day shoot in Culver City, CA. “It was kind of cool, this two-person scene. I mean, there’s no money. But it’s sort of old school filmmaking. It was bare bones, a couple of walls. A piece of glass.”

Here’s an exclusive peek at Blue, which can be found on You Tube’s WIGS channel. The current season of Blue ends April 5 and also stars Mark Consuelos, Holly Robinson Peete and Kathleen Quinlan.

Meanwhile, Petersen is as surprised that CSI will return for another season on CBS (“I didn’t think there was any reason for it to go this long”) as he is that Gil Grissom continues to pop up on the show. (The most recent shout-out occurred last month in an episode titled “Forget Me Not”).

“I didn’t even know he married Sara!” Petersen tells EW. “I found out later on. How nice! That was never my intention for Grissom. You are in the hands of puppeteers, and after a certain point you aren’t sure what’s going to happen to your puppet.”

That’s why Petersen isn’t so keen about the idea of returning to the show if and when it finally signs off CBS. “I didn’t want it to be like he’s back, he’s not back,” Petersen continued. “It should be a clean break, leave when you’re supposed to. It’s like breaking up with a girlfriend. If you keep calling her every month, you’ll never move on!”