The frog dance is at the end of Act I, and it does fit in because they're riding in a boat and start hearing the frogs and its this whole big thing that I won't get into only because people probably don't want to know the whole plot before they get there. So, basically all I'll say is they're riding on a boat through the river STYX in Hades and they run into these frogs.
And hang on, when did you win the discus?