"Sixteen" is an urban thriller about an African former child soldier called Jumah (Roger Jean Nsengiyumva) was brought to London by Laura (Rachael Stirling), an aid worker who he now lives with. Jumah is about to turn 16 in two days and wants to leave his violent past behind him. Things seem to have taken a turn for the better with Jumah now; he has a sweet but tentative romance blossoming with a girl at school. But then Jumah witnesses a stabbing and the people involved want to make sure that he says nothing to the police about what he saw that night. Pressure mounts as violence forces it's way back into Jumah's life.