This new documentary series kicks off on Channel 4 tonight that is well worth investing in. Filmed like a drama, it will be shown over the next three consecutive nights. For those that were fans of the podcast Serial, this is a similar kind of thing. Over the course of 18 months it follows a police investigation into the murder of a 19-year-old Bristol student, weaving together the stories of a detective facing an apparently motiveless crime, a family desperate for justice and another who will do anything to save their son from a life behind bars. On March 5, 2014, Nicholas Robinson was attacked and made a 999 call before collapsing and dying from multiple stab wounds. So who would want to kill him, and why? Could a single black glove found at the crime scene provide the answer?