Adam/Felicia (Guy Pierce) is the most immature (and annoying) member of the group. He's balanced out by the more mature Bernadette, in a brilliant turn by Terrance Stamp. Tick/Mitzi - played by a pre-Lord of the Rings/The Matrix Hugo Weaving - is the husband of the Hotel Owner that they're going to be playing for - although the other two don't realize this or even that he's actually married.
The film is a quasi-musical, with the group frequently lip syncing in outrageous costumes to songs by Abba. The film is wildly over the top, but with enough scenes of pathos to keep it grounded. It contains enough scenes high lighting the bigotry trans and cross dressing individuals to get the point across, but does not dwell on this theme.
See this movie, it's fun and entertaining. Features some memorable acting, awesome costumes, great musical numbers, and a story that never grows old.