Actor Bradley Cooper spent a month with police officers attending call-outs to prepare for his role in upcoming movie The Place Beyond The Pines.

The Hangover star plays a cop-turned-politician in the crime drama, and he got into character by riding with real life officers.

He tells The Hollywood Reporter, "(I was) going into these domestic disturbances, which are about 80 per cent of the calls. There was one house with a fish tank that a shoe had been thrown through. Dead fish were everywhere - and kittens were eating the dead fish as we walked by."

Cooper almost missed out on the role due to other commitments, but director Derek Cianfrance ensured he got the star he wanted by driving from New York to Montreal to personally convince the actor to take the job.

The moviemaker recalls, "We had an epic four-hour dinner where we just talked about this guy and about working together, and he decided there and then to do it."

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