Mark Andreas Sheppard is an English actor and musician. 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.

Supernatural is an American television series created by Eric Kripke. It was first broadcast on September 13, 2005, on The WB, and subsequently became part of successor network The CW's lineup. Starring Jared Padalecki as Sam Winchester and Jensen Ackles as Dean Winchester, the series follows the two brothers as they hunt demons, ghosts, monsters, and other supernatural beings. The series was produced by Warner Bros. Television, in association with Wonderland Sound and Vision. Along with Kripke, executive producers have been McG, Robert Singer, Phil Sgriccia, Sera Gamble, Jeremy Carver, John Shiban, Ben Edlund, and Adam Glass. Former executive producer and director Kim Manners died during production of the fourth season.