I'm thinking the show is Chitty-Chitty Bang bang by the "fantasmogorical" clue. I don't know the composer though.
If Percy Blakeney were in Les Mis....
Percy: Sink me! If it isn't Javvurt!
Javert: Zsah-vair, it's pronounced Zsah-vair.
Pecry: But it's spelled J-A-V-E-R-T Javvurt.
Javert: Repeat after me Zsah...Zsah....
Percy: Oh! Zsa-Zsa! Like the Gabor sister! Well I personally have always prefered Eva.
Javert: (Looks for gun)