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High School Musical alum Corbin Bleu has graduated to the big leagues and snagged a guest spot on the upcoming third season of Blue Bloods, ETonline has learned exclusively.

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The 23-year-old will guest star in an October episode as Officer Blake, a young cop who accidentally shoots and kills an innocent man. Blake suffers from severe emotional distress following the shooting and finds himself in Frank Reagan's (Tom Selleck) path.

Bleu previously guest-starred on another hit CBS drama, playing a Lockhart/Gardner defendant in a 2010 episode of The Good Wife.

Season three of Blue Bloods will premiere September 28 at 10 p.m. on CBS.