“Calling Mumia” is a collaboration between Snoop and 3D from Massive Attack (“100 Suns” is MA’s music production company) for the forthcoming Marc Evans-directed documentary In Prison My Whole Life. The storyline: A dude (Will Francome) born the day Mumia Abu-Jamal was arrested in Philadelphia for the alleged murder of a police officer, Daniel Faulkner, investigates the case, trying to imagine what it’d be like to be on death row his whole life (25 years so far). Abu-Jamal’s maintained his innocence since being locked up, and a lot of folks believe him: The film includes talking heads like Noam Chomsky, Alice Walker, Mos Def, Snoop, and Angela Davis. It also includes this track (pretty great production), which you can hear at massiveattack.com. The movie opens in the UK this weekend.