Mark Sheppard
Mark Andreas Sheppard (born 30 May 1964) is a British actor and musician. He is often credited as Mark A. Sheppard. Sheppard is known for playing the demon/King of Hell Crowley on Supernatural and for his recurring roles as lawyer Romo Lampkin on the Battlestar Galactica reboot, Interpol investigator James Sterling on Leverage, and small-time crime lord Badger on Joss Whedon's Firefly. Description above from the Wikipedia article Mark Sheppard, licensed under CC-BY-SA, full list of contributors on Wikipedia.
Filmography
Supernatural
NCIS
CSI: Crime Scene Investigation
Doctor Who
24
Medium
The X-Files
Charmed
Monk
Star Trek: Voyager
Without a Trace
White Collar
The Practice
Burn Notice
Battlestar Galactica
MacGyver
Las Vegas
Chuck
Warehouse 13
V.I.P.
Sliders
Leverage
Doom Patrol
Silk Stalkings
Shark
Dollhouse
Firefly
Martial Law
In Plain Sight
Secret Level