It's hard to put your finger on this one. Basically I suppose it's a comedy about an idle rich drunk who falls in love with a (comparatively) poor girl, whom he wants to marry at the risk of being disowned by his family.
It has funny moments, romantic moments, and touching moments. Dudley Moore is funny and somehow makes his self-centred character endearing, Liza Minelli is a convincing foil as the the feisty opposite he attracts, but John Gielgud steals the show as Arthur's wonderfully sarcastic butler.
It's corny but great fun with a memorable soundtrack, and ran for nearly 3 months at our local fleapit.