William S. Gilbert was a frightful tease. He dangles before you a ­blatant satire on the evils of the rich that turns out to be no such thing, and then turns his withering parody on that softest of targets, the low-level Victorian melodrama (resolving itself with a witches’ curse finessed by a point of law and the most passionate of the protagonists electing to unsex themselves and move to the prim death-in-life of Basingstoke). What’s it all about? Ruddigore appeared in 1887 and has always been seen as a problem piece, though these days we are likelier to enjoy its mixed tone and iffy subtexts than our ancestors. This small-scale (10 singers and a piano) version in a north London pub again makes the case that the piece is way stronger than its ­reputation. The idea is