Law and Order 24x03 sees Riley's brother caught up in a case (Which NBC star is playing Matt?)

This season on Law and Order Riley is dealing with some shake-ups and they're coming quite early in the procedural's twenty-fourth run. The premiere, "Catch and Kill," saw Lt. Kate Dixon exit off-screen with the detective unaware that his boss was looking to leave. She did check-in later, letting him know she'd moved to Florida with her son but her departure blindsided him nonetheless.

Now, in episode 3 "Big Brother," Riley has to contend with his brother Matt being involved in a case. Thankfully, Matt's not the victim of a crime but it does seem like he may obstruct justice in the name of not snitching. Check out the promo below!

Ryan Eggold is Matt Riley on Law and Order season 24

Longtime viewers of NBC will recognize New Amsterdam's Ryan Eggold is guest starring in this episode. He's playing Riley's brother who may know more than he's willing to share with him or the prosecution. Apparently, Matt is the last person who saw the victim alive, however, the teaser implies that the suspect is a friend of his so he's caught between a rock and a hard place. It's enough to get Price yelling in the courtroom reminding Matt that his silence could mean a murderer walks free.

The synopsis states that Price takes a chance on a witness who could speak to a hidden motive for the murder. That may be Matt. If it is, perhaps this case isn't a simple one and Matt is staying quiet out of loyalty not some need to follow street rules. Either way, "Big Brother" is sure to be a good episode for Riley as it'll introduce more backstory for him and establish a new family dynamic on Law and Order.

Eggold is also an excellent actor. He starred as Dr. Max Goodwin in New Amsterdam, a medical drama focused on the titular hospital and its staff who provided life-saving care to their patients. Often unorthodox and trying the patience of the hospital's board, Max made a point of putting patients first and lived by the motto of "How can I help?" The series ended in 2022. NBC is developing a spinoff set in the near future that would focus on Max's daughter Luna and her work as a doctor.

Besides this guest starring role on Law and Order, you'll be able to catch Eggold in another crime drama in November. He plays Ed Ramsey in Cross, the Prime Video adaptation of the popular James Patterson character's story.

Law and Order season 24 episode 3, "Big Brother," airs Thursday, Oct. 17 at 8 p.m. ET on NBC. Next day streaming will be available on Peacock. Stay tuned to Americans Undercover for coverage. Follow us on X and Facebook for more content!