Reaching central London, the actor and presenter boards an industrial working ship on the Thames, learning it is a route not without risks as ships must squeeze under bridges at high tide and avoid running aground at low tide. At the Chelsea embankment, Tony explores the Physic Gardens where early botanical remedies were created from exotic plants brought in by river from all over the world. On the south bank, he goes mudlarking, scouring the shore at low tide for objects discarded by revellers past, before getting a bird's-eye-view of the river from the Shard. Tony's final stop is Tower Bridge.