1. AWOL
The team investigate a missing persons case when a soldier suffering from PTSD fails to turn up to his mother's funeral.
Suspects — Season 4
2. Revenge
The team reopen an old case of a fatal stabbing, after a criminal involved in the original attack is left for dead in a copycat crime.
3. Ricochet
The team are shocked by the shooting in broad daylight of a popular clergyman outside the boxing club that he runs for disaffected youths. Martha suspects that the vicar’s hug-a-hoodie approach has backfired - but the investigation soon moves into far darker territory…
4. Rough Justice
When an elderly widow is brutally attacked in her own home on a notorious London estate, the team set out to find her attacker.