Crossword Genius

Musical whose preshow warning about cellphone use says that knights “may drag you onstage and impale you” (8)

Ross

I believe the answer is:

spamalot

(Another definition for spamalot that I've seen is " Monty Python musical".)

I've seen this clue in The New York Times.
Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.