Note: This is the audio soundtrack of the TV story, with linking narration by Katy Manning. Not to be confused with the audio reading of the novelisation, released in 2012. Had previously been released on the Monsters on Earth box set. Subsequently re-released as part of the Classic TV Adventures: Collection One box set.
"We shall destroy Man and reclaim the planet!"
Visiting the Master in his high-security prison just off the south coast of England, the Doctor and Jo Grant's curiosity is piqued by a recent spate of disappearing ships. Investigating a nearby sea fort, they encounter a ferocious amphibian creature — the cousin of a reptile race whom the Doctor met once before.
These 'Sea Devils' have been revived from hibernation by the Master, whose scheme is being aided by the prison governor. Realising that the Master wants to create havoc on Earth, and to see humanity subjugated by the Sea Devils, the Doctor once again attempts to broker peace between the two races.
But his efforts are hampered by the intervention of a government minister, whose sole aim is to wipe the sea creatures out. Battle ensues at sea and on shore, and control of the planet once more hangs in the balance...
In an additional bonus interview, Katy Manning, who also provides linking narration for the story, recalls making The Sea Devils for television.