One of the great divides amongst viewers of Doctor Who (in both its classic and current incarnations) is between those who view it as an avant-garde, cult science-fiction show, and those who view it as a slightly goofy show whose main appeal is that it is a family program. And a large part of this divide is between American fans of the television show, where viewers have probably found out and become devoted to the show through geek circles, and British viewers, where the show is usually one of the most watched shows on Saturday evenings.
All of this brings us to "The Idiot's Lantern", the seventh episode of the second series of Doctor Who, starring David Tennant as The 10th Doctor.
The synopsis of the plot is that The Doctor and his companion, Rose Tyler, end up in London during the coronation of Elizabeth II. This being a Doctor Who episode, this historic occasion is being marred by a grotesque alien invasion plot, where televisions (a new invention, but being bought up so that people can view the coronation) are being possessed by an electronic entity of some sort, who erases people's faces. The whole thing is being hushed up by the police, and there is an entire subplot about a domineering father who tries to hide his mother-in-law's infliction with facial erasion. All of which is, of course, solved by The Doctor, who climbs up a radio tower and reverses polarity, and then everyone enjoys the coronation and gets their faces returned.
And this is where the dichotomization of the show's audience becomes a key influence. As an American science-fiction fan, I wonder why a television show that conceptually has so much more ground to explore than any other show, ever, should so frequently end up in suburban London. This is especially the case since much of the basic plot of the episode (Doctor shows up in London for an important national event during a string of disappearances) is used again in "Fear Her". But for the family viewer, the episode's construction makes more sense. The average family sitting on the couch on Saturday evening isn't going to be up on Gallifrey and the Time War and paradoxes and timey-wimey balls. Instead, they are given a familiar setting, a familiar event, some earthly domestic drama, and The Doctor being just a visiting figure, who manages to solve the problems in the episode's forty-odd minute span.
So whether this episode succeeds or fails depends on which audience you are part of. As an American who is watching the entire series on DVD, it seems like filler that fails to use the possibility of the Doctor Who concept as it could. If I was a member of the British general audience who was looking for an entertaining fantasy that had an easy to understand setting, I would say that it succeeded.