Line of Fire Episode 5, titled Cul-de-Sac, will air on NBC on October 19. According to Rotten Tomatoes, the official synopsis for the episode reads as follows:"Clare goes undercover with a new partner; Jane and Nia search for a mole in the Task Force; Russ and Micah unearth new evidence in the Barnes assassination attempt."According to the Episode 5 preview shared by TV Promos, Emmy Award-winning actor Sam Waterston, best known for playing Jack McCoy in Law & Order, will guest star as former President Thomas Barnes. The Line of Fire premiere teased that Mike Hollingsworth is haunted by Barnes' attempted assassination six years ago, which will likely be explored in the upcoming episode.Here's what to expect in Episode 5.Sam Waterston will guest star in Line of Fire Episode 5In August 2026, Deadline reported that Line of Fire added Sam Waterston in a guest role. It's time for the Law & Order alum to appear in the police procedural.The teaser for the fifth episode puts former President Thomas Barnes in focus, as Russ and Micah uncover new evidence in his assassination attempt six years ago. The upcoming episode will likely address the mystery teased in the premiere. The premiere established that Deputy Special Agent Mike Hollingsworth in the U.S. Secret Service was inches away from retirement, but an old case was still keeping him up at night.The preview for Episode 5 hints that Mike thinks they 'got the wrong man' in Barnes' attempted assassination, meaning the real killer is still out there. While it remains to be seen whether the former President agrees with Mike's theory, Russ and Micah certainly trust their father's hunch, which sets up another mystery in the procedural.On the other hand, Jane will team up with Wallace to uncover the truth behind the origami cranes left at the crime scene. In the latest episode, Jane confessed the truth about Jack to Wallace, as she believes that somebody is using her stepson's identity. As the mystery around the cranes increases, Jane and Wallace will team up in the upcoming episode to catch the mole in the Task Force and uncover the connection between Jack and the recent killings.Line of Fire Episode 5: Release date and streaming detailsLine of Fire releases weekly episodes every Monday on NBC. The fifth episode will air on NBC on October 19 at 10:00 PM ET.Cord-cutters, worry not. You can stream the episode on Peacock, NBC's official streaming partner, a day later. The platform offers three types of plans: Peacock Select, which costs $8.99 per month/$89.99 per year; Peacock Premium, which costs $12.99 per month/$129.99 per year; and Peacock Premium Plus, which costs $19.99 per month/$199.99 per year.Who's in the cast for Episode 5? View this post on Instagram Instagram PostLine of Fire Episode 5 will mark the return of the procedural's main ensemble, which includes Peter Krause as Mike Hollingsworth, Hope Davis as Jane Hollingsworth, Kat Cunning as Clare Hollingsworth, Tommy O'Brien as Mike "Micah" Hollingsworth Jr., Taylor Bloom as Russ Hollingsworth, Charlie Barnett as Jack Hollingsworth and Antoinette Crowe-Legacy as Nia Wallace.Sam Waterston's guest appearance is shaping up to be one of the most intriguing parts in the upcoming episode. It marks the veteran actor's return to the small screen after two years, following his appearance in over 400 episodes of Law & Order.Tune in to Line of Fire Episode 5 on NBC on October 19.For the latest scoops on your favorite TV shows and movies, follow SoapCentral.