Ben Stiller has been regularly revealing new cast members for his comedy sequel Zoolander 2 through his social media pages ever since shooting began last month. Today the actor/writer/director/producer shared a new photo on his Instagram page, featuring his character Derek Zoolander staring down pop star Justin Bieber, who has joined the cast. The musician's role has yet to be revealed, so it's possible that he could be playing himself in a cameo, or he could also be portraying a blue steel rival of Derek's.

Regardless of who Justin Bieber is playing, he joins a cast that also includes Owen Wilson, Christine Taylor, Penélope Cruz, Cyrus Arnold, Billy Zane, Fred Armisen, Kyle Mooney, Kristen Wiig and Olivia Munn. The sequel will mark Justin Bieber's first major movie role, although he did have an uncredited part in last year's Behaving Badly, which starred his ex-girlfriend Selena Gomez. He also had a two-episode arc on CSI: Crime Scene Investigation, had a guest voice role on The Simpsons and provides the voice of K.I.T.T. in the upcoming Killing Hasselhoff. Of course, he also starred in the feature-length concert documentaries Justin Bieber: Never Say Never and Justin Bieber's Believe.

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Ben Stiller is directing Zoolander 2 from a script he co-wrote with Justin Theroux. Other actors such as Jonah Hill, Kanye West, Kim Kardashian, Cara Delevingne, Naomi Campbell and Anna Wintour have been rumored to have cameo or supporting roles in the sequel, with Will Ferrell also believed to be returning as Mugatu from the original Zoolander. While we wait for Ben Stiller to reveal the next cast member, take a look at his photo with Justin Bieber below.