Oh crap! Did the Doctor cease to exist when the two fluxed ships separated?
Of course not. He passed out somewhere. Heck, the confusion allowed Romana to escape that customs agent. All that’s left now is to somehow get the Mandrels off the cruiser and catch the real drug smugglers.
That would be Professor Tryst and Dymond, the captain of the survey ship. Tryst was selling drugs to pay for his research, and while the Doctor normally is all for scientific research, he draws a personal line at people using human misery to pay for it.
Besides, he woke up on the survey ship and rode back to the cruiser by literally sitting behind Dymond on the shuttlecraft and mostly being glad that guy never looked behind himself to check for stowaways. That more or less works, too, even if it is a rule violation for living in Zombieland. Once back on the cruiser, everything works out pretty well. The Doctor and Romana clear Della’s name, and then Stott does the same for the Doctor. But then, Tryst and Dymond were planning on using a special laser to transport Eden to the survey ship, from which they could fly off and sell more drugs.
However, the Doctor has used K9’s dog whistle to lure the Mandrels back to Eden, closed it off, and with Romana, reversed the laser to zap the survey ship’s bridge back to the cruiser’s station. Tryst got caught by his own interdimensional whoozywhatsit, and he and Dymond are under arrest.
All that’s left is for the Doctor, Romana, and K9 to use the TARDIS to return all of Tryst’s specimens back to whatever planet they came from, including the Mandrels since it wasn’t their fault people were making narcotics out of them.
So, I guess everything worked out fine. You know, as long as you aren’t an interplanetary drug dealer killing large alien monster men to fuel the addictions of other people.