Ghostbusters II (1989)

Catching up with the team to see what has become of them in the interim between first and second film, we learn that following their successful saving of New York last time round, they ended up being accused of causing the mayhem, and landed with the bill for repairs.
Ramis has by this time returned to academia, Murray hosts a cheap daytime paranormal TV show (the extract we see is probably the highlight of the film), and the only two to remain with the old firm are Ackroyd (who also runs an occult book shop) and Hudson. The business, however, has declined to the point that they are now children's entertainers, and not even very successful ones. This is all splendidly inventive stuff - vastly more amusing and self-justifying than the average cash-in sequel.
All the more disappointing, then, that half an hour in it switches gears again and takes off in precisely the reverse direction, becoming more of a remake than a sequel. Virtually every successful idea and set-up from the first film is repeated in the thinnest imaginable redressing, and old characters are shoehorned into the screenplay more from commercial than narrative necessity. The very few new ideas are mainly unsuccessful, and that relaxed chemistry among the cast that made the first film such pleasant viewing feels just a little forced this time around too. But it's still good fun if you were there.