Meet the Feebles (movie, 1989)

Heidi, the star of the "Meet The Feebles Variety Hour" discovers her lover Bletch, The Walrus, is cheating on her. And with all the world waiting for the show, the assorted co-stars must contend with drug addiction, extortion, robbery, disease, drug dealing, and murder. Meanwhile the love between two of the stars is threatened by Trevor the Rat, who wishes to exploit the young starlet for use in his porno movie.