The investigation of the murder of Christopher Collins, who was listed on a website as missing by a former employer, meets a dead end until it is revealed that he was in the witness protection programme. Meanwhile, the team wonder what effect the upcoming cuts to the police force will have on UCOS.

The team reopen the case of zookeeper Zac Halsey, originally thought to have been mauled to death by a tiger, when blood evidence discovered in his lodgings suggests he was killed before he was found in the tiger's enclosure.