Radio has to be one of the most un-cinematic things on the planet; it's a guy sitting in a booth for four hours talking into a microphone, or maybe playing some music. And yet radio has a kind of special magic about it. A person's voice comes sailing through the airwaves and landing in our homes, and it has the power to captivate, to soothe and to make sense of the world. Radio has appeared in a surprising number of good movies: Wolfman Jack and Stephen Wright, respectively, provided atmosphere in American Graffiti (1973) and Reservoir Dogs (1992), Robin Williams brought humor to the troops in Good Morning, Vietnam (1987) and Christian Slater brought hope to high school students in Pump Up the Volume (1990).

It's probably a great deal more difficult to make a movie about podcasting, and so with her new film Talk to Me, director Kasi Lemmons (Eve's Bayou, The Caveman's Valentine) returns to the past for the story of Ralph "Petey" Greene (Don Cheadle), an ex-con who became one of Washington DC's most recognizable personalities in the 1960s and all the way up to his death in 1984. Lemmons starts her movie with a bang, with Petey's signature line: "Wake up, Goddammit!" as Dewey Hughes (Chiwetel Ejiofor) rolls out of bed, puts on his suit and makes an excursion to prison to visit his brother (Mike Epps). Lemmons intercuts Dewey's progress while Petey "raps" about imprisonment. Dewey may be free, but he's trapped, too.