When The Doctor leaves Professor Litefoot and Leela in the cab as he goes off to explore the Palace Theatre, it begins a cycle of rotating companions for The Doctor over the next few episodes. After bandying theories back and forth with Professor Litefoot in the morgue, The Doctor meets up with Henry Gordon Jago (whose name is so delectable that Tom Baker, and this reviewer, cannot help but use in full at any given opportunity) and begin poking about the depths of the theatre.
The Doctor and Jago make a great team. Jago is the bumbling idiot of the two, yet The Doctor suffers him quite gladly as he sees that, despite his failings, Jago means well. The gulf between the heroism of The Doctor and the ineffectiveness of Jago is never made more apparent during the splendid chase sequence through the theatre when The Doctor is trying to catch Magnus Greel. While The Doctor is swinging from curtains to try and catch his prey, Henry Gordon Jago is whacked on the back by Greel and left sprawled out on the floor for most of the chase. The Doctor's wonderful demeaning of Jago as he picks up the chase ("Cheer up, Jago! Cheer up!") is blissful.
Meanwhile, Litefoot and Leela of some just lovely scenes in the Professor's dining room as the morals and manners of Leela's savage upbringing clash with Litefoot's upper class leanings. My favourite bit is when Leela picks up a chunk of meat and starts showing down on it, sans any cutlery or plates. Because Litefoot is unfailingly polite, he hesitantly picks up a side of beef and eats as Leela would. Part of having good manners is to not embarrass your guests, after all. However, by the time Leela takes a big gulp from a serving bowl, Litefoot feels comfortable enough to admonish her for not using a napkin.
Another charming delight of an episode.