An old man was sifting Thames bank in order to find something valuable with a metal detector: he found a gold watch together with a human skeleton. Detectives soon realized it is related to a missing person who was declared dead nine years before and a man (Iain Glen) had just been convicted for the murder. By chance the prosecutor at this time was the actual prosecutor Steel but there are many things to be cleared: the victim was shot in the skull, the killer didn't slide his throat as was presumed at the time; besides the murder place was not Chelsea but Tower Hamlets where the body is located. The convicted man managed to obtain a retrail thanks to his law knowledge (he have been studying laws during all this time spent behind bars). Steel struggle to find out further evidences in his support, but it's a long road and time is a wasting.
This episode displays how much been an educated person counts. The perp was able to set prosecutor up due to his reading time in the joint, where he had a lot of time to organize his revenge.
