In or on Romeo and Juliet

I have heard that if you are talking about a TV show, you need to use "on". For example, suppose that You Cook is the name of a cooking show on TV. I think you need to say,

(1) On You Cook, some of the chefs make interesting dishes.

If you are talking about a novel, a play, or a movie, do you use "in"? For example,

(2) In Romeo and Juliet, some of the characters are interesting.

Are the prepositions in both sentences correct? Thanks a lot.