1. Episode 1

Tony begins his journey at the source of the Thames in Gloucestershire. He meets a professional crayfish catcher, investigates the cleanliness of the water and discovers the uses the Home Guard put the river to in WWII.

3. Episode 3

Reaching central London, Tony Robinson boards an industrial working ship, explores the Physic Gardens, and gets a bird's-eye view of the river from the Shard.

4. Episode 4

On patrol with the Metropolitan Police Marine Unit, Tony gets an emergency call-out to an unexploded bomb. At Billingsgate Fish Market, he relives his teenage years working the docks.