Cameron Riley Monaghan (born August 16, 1993 in Santa Monica, California) is an American actor.
A former child star who played bit parts in film and television, he's perhaps best known for his role as Ian Gallagher in the Showtime series Shameless, as well as for playing Jerome Valeska (a proto-Joker of sorts) in the Batman prequel series Gotham. He would later play the true Joker, aka Jeremiah Valeska, Jerome's twin brother. Monaghan also provided the voice and likeness for former Jedi Cal Kestis in the video game Star Wars Jedi: Fallen Order and its sequel, Star Wars Jedi: Survivor.
- Malcolm in the Middle (2004-2005) as Chad
- Ned's Declassified School Survival Guide (2005-2006) as Palmer Noid
- Criminal Minds (2005-2020) as Jeffrey Charles
- Click (2006) as Kevin O'Doyle
- NUMB3RS (2009) as Todd
- The Mentalist (2009) as Elliot
- Monk (2009) as Danny Cooper
- Three Rivers (2009) as Auden Drinkwater
- Fringe (2009) as Tyler Carson
- Shameless (2011 — present) as Ian Gallagher
- Prom (2011) as Corey Doyle
- Vampire Academy (2014) as Mason Ashford
- The Giver (2014) as Asher
- Gotham (2015 - 2019) as Jerome Valeska (The Proto-Joker) and Jeremiah Valeska (The Joker in all-but-name, this is due to some very complicated legal issues with Warner Bros. that didn't allow his name to be used at the time).
- Mercy Street (2016 — present) as Tom Fairfax
- Amityville: The Awakening (2017) as James Walker
- Reign of the Supermen (2019) as Superboy
- Star Wars (2019 — present) as Cal Kestis
- Tomorrowverse as Kamandi