With my high level of weasel solipsism I cannot remember whether this is an idea I was idly musing about, or whether it comes from a story or TV series or something, and if so what, so I welcome any thoughts as to where it might have come from. The idea is that there are humanoid aliens amongst us (who can pass for humans), they have some high technology e.g. the ability to cure diseases, but they don't use it very much, only as a favour to people, kind of thing.
The main thing about them is that they are quite dull and literal minded, not humourously so in the manner of tedious comedy sketches, but just rather dull.
The alien in the latest Jasper 'like him or hate him' Fforde is vaguely on these lines, but the idea definitely pre-dates that.