Keira Knightley Caught Kissing Mark Ruffalo

James Righton, look away now! That's your fiancée, Keira Knightley, smooching with co-star Mark Ruffalo on the New York City set of their new movie, Can A Song Save Your Life?

The film, produced by Judd Apatow, also stars Maroon 5 frontman Adam Levine as Knightley's musician boyfriend, who leaves her when he decides to embark on a solo career without her.

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