Release Message:  The TARDIS arrives at the marsh planet "Delta Magna", where the Doctor (Tom Baker) and Romana go in search of the fifth segment to the Key to Time.

Description:  The TARDIS arrives at its next destination, the marsh planet "Delta Magna", where the Doctor and Romana go in search of the fifth segment to the Key to Time. They discover the native tribal Swampies worship Kroll, a gigantic squid as a god, only to find Kroll has accidentally swallowed the fifth segment and Romana is chosen by the Swampies for sacrifice and The Doctor sets out to save a local refinery from being attacked by Kroll.