Command that could be given to the title characters in 17-, 26- and 45-Across?

The answer to this crossword question is a playful command that could be given to the title characters in 17-, 26- and 45-Across, and the phrase is “BREAKITUPYOUTWO“. The word “break it up” is often used to describe the act of separating two people who appear to be getting too close or who may have an argument or disagreement. In the context of this crossword question, the answer is a fun way of suggesting that the characters in the referenced clues should end their relationship or part ways in some way. It’s a clever play on words that adds some humor to the puzzle.