The search is on to find the missing suspect. Linda and Walti revisit an old case in an attempt to gain the upper hand over Waingrow. After weeks of speculation, the events surrounding Angela's murder are finally revealed.
The net closes in around Dr Crowley. Fresh testimony helps the investigation - but reveals a secret from Linda's past.
Lucy reveals a secret past which devastates Bobby, while police in Germany and the UK make a breakthrough involving drug trials.
Bobby arrives in Dusseldorf to uncover the mystery surrounding Ruben Locana's death. Chasing a lead turns out to have catastrophic consequences for one of the detectives on the case.