Darkness Visible: Part 1

Plot:

Sam investigates the death of a gay man while in police custody. He had been arrested while drunk and was sharing a cell with another drunk, in for the night. The victim died from a blow to the head and was badly beaten post-mortem. DS Farmer is concerned that the assault may have been the work of some of her officers. Sam also meets up with Liam Slattery an old friend she has not seen for 20 years. Sam's sister however is convinced Liam was responsible for the death of their father years before.