Justin Long Joins Ex Drew Barrymore at Her Movie Premiere

Justin Long helped ex Drew Barrymore celebrate at the NYC premiere of her new HBO flick Grey Gardens.

Asked what it was like to have him there, Barrymore -- who will soon shoot the comedy, Going the Distance, with Long -- smiled and quickly walked into the theater with costar Jessica Lange.

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In the movie (premiering Saturday), Barrymore plays Little Edie, the reclusive cousin of Jacqueline Onassis Kennedy who lived in squalor with her mother, Big Edie (Lange).

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To prepare for the film, Barrymore told reporters, "I went away for three months and I cut myself off from rest of the world to literally understand what being isolated is like and not live in a world with technology and not have friends and family surrounding me."

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Asked how it was working with Barrymore, Lange told Us, "Amazing. It was a real experience working with Drew a great one!"

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