16 Bars is a feature-length music doc that offers a rare glimpse at the human stories — and songs — that are locked away in our nation’s jails and prisons. In a Virginia jail’s makeshift recording studio, four men collaborate on an album with Grammy-winning recording artist, Todd “Speech” Thomas, from the hip-hop group Arrested Development.

With the U.S. locking up more of its citizens per capita than any other nation on the planet, the music of 16 Bars serves as rare testimony to the raw and messy truth behind the criminal justice system‘s revolving door.