Thanks for those hints. Unfortunately no lights are flahing in my brain.
"Pet on the way" seems as cryptic as the rest of the clue. Is 17 across the title of an opera, or an opera company?
I'm beginning to wonder if my 24 and 28 entries are correct.
For 24 I have the surname of a very well known comedian ; and for 28 a citric fruit. Ah, does 28a end in R?