The CW Network mainstay Supernatural has promoted Mark Sheppard, who plays The King of Hell named Crowley, to series regular for Season 10.

The actor has recurred as Crowley since Season 5, appearing in 35 episodes of the series since 2009. The character played a major part in the show's Season 9 finale, "Do You Believe In Miracles?", which ended with Dean (Jensen Ackles) being turned into a demon under Crowley's watch.

Misha Collins, who plays the fallen angel Castiel, was also promoted to series regular earlier this week. The actor had previously recurred in Season 4 and Season 8, and was a series regular in Season 5, Season 6 and Season 9.

The show was given an early renewal for Season 10 back in February. The CW also ordered a spin-off series, Supernatural: Bloodlines, to pilot, but the network passed on the show earlier this month. The network is entertaining other spin-off possibilities at this time.

Mark Sheppard has previously appeared in hit genre shows such as Battlestar Galactica, Doctor Who and Firefly.