Since I've been watching this very good 1950s Sherlock Holmes TV series, I've found "The Christmas Pudding" to be one of the finer episodes, even though it is rather atypical and its strangeness are not all the same as those of the other episodes.
The episode unusually begins in media res, with Holmes and Watson already attending the trial of a criminal, and this deviation in a series that has mainly followed the tradition of beginning with the two in the Baker Street rooms works very well. In fact, this entire episode is not much of a whodunit and more of a how-will-he-do-it, with John Norton the criminal threatening to escape and kill Holmes. We can guess pretty easily that his wife has slipped him something in the titular Christmas pudding as we are familiar enough with that trope, but it doesn't detract from the suspense.
Strangely for a Christmas episode, this one features little of the humor that characterizes these incarnations of Holmes and Watson. Instead it is played very straight and for suspense, which it gets. Even Eugene Deckers, which has been hilarious in some previous episodes, is instead very threatening here.
It is strange to see Sherlock Holmes falling pray to irrational fears, but somehow Howard and Crawford pull it off. Holmes' deception to get Watson to clear out of 221B so that he will be out of danger is actually rather touching. Interesting to note that this is also unusual because, strangely in this series, Inspector Lestrade does not appear.
This is a very well done episode, and good viewing for those who like a little murder and jailbreak at Yuletide.