The “Cities of Love” series is like a travelogue on film, complete with little notes from stilted lovers and letters to new crushes. Paris, I Love You had charm to spare but each of them since has degraded over time. Berlin, I Love You, while still worthwhile for its kookier bits, might be the worst of them. Featuring Keira Knightley, Luke Wilson, Mickey Rourke, and Jim Sturgess, among others, in a series of vignettes around the grey decay of Berlin’s slums and the bright lights of the city’s great high rises, it’s an obvious ode to the Paper City as well as a rote love letter to the people that inhabit it, namely Americans and Englishmen. For a film about Berlin there are very few Germans in it. Then again, maybe that was for the best given the best parts belong to Sturgess and Rourke. The latter proves he’s still got life left in him as a genuine actor and movie star, and Sturgess gets the kooky bits as a man receiving life advice from a self-driving car with a mind of its own. That slice of science fiction occasionally sets apart a film that would otherwise come off like a collage of Hallmark cards, a Hallmark movie with better actors and too many vignettes.