Doctor Who: The Curse of Fatal Death

The story begins with the Master gloating over his latest scheme to destroy his nemesis. However, instead of only spying on the Doctor and his companion Emma, he is actually in communication with them, so they hear his plans. The Doctor invites his old foe to meet him at a castle on the planet Tersurus. The planet is in ruins, and was the home of a now-extinct race of supremely-enlightened beings shunned by all because they used flatulence as their means of communication. They all died when they discovered fire.