This story is from the age when the Tom Baker era was going downhill, but I'd say it's the best I've seen of the Key to Time season. Okay, so the special effects aren't all that awe-inspiring, but who watches Dr Who for the special effects? The story, involving tribal worshipping of a god who turns out to be an outsized squid-like beast and the invasion of a primative culture, is well-written and entertaining. Tom Baker is at his best, and the final episode is a blast.