
Mike Doyle (born September 16, 1972) is an American actor, screenwriter, director and producer. He is best known for his recurring roles in the television series Law & Order: Special Victims Unit, playing Forensics Tech Ryan O'Halloran, and Oz, playing Adam Guenzel.
It was on the set of Oz that Doyle met George Morfogen, whom he would cast in Shiner, a short film written, produced and directed by Doyle that debuted at the 2006 Tribeca Film Festival. Doyle also wrote and produced the 2003 limited-release film Cutter.
Doyle played Lt. Cmdr. Tom Palatonio in the 2005 action film Phantom Below, which is notable for having been released in multiple versions under multiple names which included or excluded gay content depending on the edit (the gay-themed edit was released under the title Tides of War). Also in 2005, he plays a gay coffee barista named Andy in 29th and Gay.
On June 2, 2009, The New York Times published an article about Doyle and his tendency to die on screen during his acting roles. His seventh death, in the season 10 finale of Law and Order Special Victims Unit, ended a successful six year run as forensic tech Ryan O’Halloran on the show.

Green Lantern
2011 · as Jack Jordan

Rabbit Hole
2010 · as Craig

P.S. I Love You
2007 · as Leprechaun

The Invitation
2016 · as Tommy

The Kill Room
2023 · as Raphael Pronto

Some Girl
1998 · as Steven

Max Steel
2016 · as Jim McGrath

XX
2017 · as Chet (segment "Her Only Living Son")

You're Not You
2014 · as Tom

Jersey Boys
2014 · as Bob Crewe

Ghost Bike
2021 · as Dean

Shortcut to Happiness
2007 · as Luke

Union Square
2011 · as Bill

Let Them All Talk
2020 · as Murray Dix

Laws of Attraction
2004 · as Michael Rawson

Red Ink
as Senator Conrad

Heavy Petting
2007 · as James

Nocturna
2015 · as Harry Ganet