New Tricks - Season 11 Episode 4 -

When Steve McAndrew's teenage son Stewie is arrested for drug possession, he finds himself face to face again with his ex-wife Tricia as they try to save the boy from a downward spiral. And after a distressed dementia patient escapes her care home to report a murder, the team look into the disappearance of a policeman, possibly murdered but missing since 1956...