One actor who appears in the new sequel to “The Devil Wears Prada” appears so unrecognizable in the film that fans are reporting they didn’t even realize it was him. And a warning — mild spoilers for  “The Devil Wears Prada 2”  below. Actor Justin Theroux’s name appears in the opening credits for the film, along with returning stars like Anne Hathaway, Meryl Streep and Emily Blunt. Justin Theroux and Emily Blunt behind the scenes of “The Devil Wears Prada 2.” Instagram/silverspotcinema And Theroux appears midway through the film in a supporting role, as a tech billionaire named Benji Barnes who also happens to be Blunt’s character Emily’s new boyfriend, happily bankrolling her latest ambitious career move. With his orange fake tan and tact-free declarations that AI will soon replace everyone’s jobs, Theroux’s character is a comically grotesque villain — and he does such a good job of it that some fans who were waiting for the actor to turn up on screen never actually clocked that it was him.…