So, the Chinese thought this guy from a mysterious time cabinet was Weng-Chiang, a god of some kind.
Yeah, there’s nothing potentially racist about that plot line.
In the meantime, the Doctor does successfully use that giant gun he borrowed from Litefoot to kill the giant rat that is trying to kill Leela. He even manages to do that without hurting Leela. So, the rat is dead! Huzzah!
Wait, there is apparently more than one, and the gun takes a half-hour to load. Time to split.
Back at Stately Litefoot Manor, the Doctor does some more thinking with Litefoot, realizing for some reason the Chinese want the cabinet. Leela got a new change of clothes, so the Doctor decides to take her to Jago’s theater and see Chang’s act in person. Considering Chang is offering to kill the Doctor for his master, that might not be a good idea.
But that never stopped the Doctor before. He manages to slip out the back (in full view of the audience) after Chang gets him as an assiatant, but the trick still goes wrong when the fake Weng-Chiang kills Jago’s assistant and stuffs that poor man in the cabinet. That leads to a chase as the Doctor and Leela follow Chang down to Weng’s hideyhole. Chang manages to slip into the sewers to escape, but there are still giant rats in there, so, yeah.
At any rate, the Doctor figured out what’s going on. Someone from the future used a time cabinet to go into the past. The trip was bad for his health, so he needs to drain young women of their life energy to stay alive. But that process just makes Weng’s condition worse. So, the cure is worse than the disease? You suck, Weng!
Or not. Mr. Sin, the tiny guy who can take a knife to the neck without slowing down, is inside Litefoot’s house. After two minions kill the policeman outside, Sin lets them in and the Doctor and Leela return to the house in time to see Weng, Sin, and some others ride off with the time cabinet…