Episode Four
Series Episode Number: 353World Premiere: Sat 9 Jun 1973 - 5:50pm BST [BBC One] (United Kingdom)
First Broadcast: Mon 24 Nov 2014 - 8:30pm EST [Retro TV]
Running Time: 25 minutes 57 seconds
6.80 Million (UK)
Chart Position: 32 () (UK)
Recorded on Tue 17 Apr 1973 in TC3
Archive State: PAL 2 VT
The Brigadier attempts to seal the giant maggots in the mine with explosives, but this only results in the creatures burrowing to the surface.