Crack in joint between molding and ceiling
I really don't want to remove and replace all the molding. Any suggestions on fixing?


If the crack has stopped growing and the wall is stable, you could just remove any loose plaster/filler, apply new filler and repaint. You'd need a "deep crack" filler.

If the crack is still growing and is as large as it looks, you have a more urgent and more important problem needing professional help.