when did the actor begin his on-screen career?
1999
Misha Collins
1999 
the supernatural played a part in the works of Misha Collins who is this character? Castiel is an Angel of the Lord, a fictional character aired as part of TV series "Supernatural."
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Misha Collins [SEP] Acting
His film work includes an uncredited appearance in the 1999 movie "Liberty Heights", as well as roles in "Girl, Interrupted", "Finding Home", "Karla" and "Loot" (on which he also served as Associate Producer). As well as his work as the angel Castiel on the CW television series "Supernatural", other television shows includes "Legacy", "Charmed", "NYPD Blue", "24", "", "ER", "Monk", and "Timeless".