Fans already know two characters will die, but a pair of famous authors pray one of them won't be Harry Potter himself.
"My fingers are crossed for Harry," Irving said at a joint news conference before a charity reading by the three writers at New York's Radio City Music Hall.
The author of "The World According to Garp" said he and King felt like "warm-up bands" for Rowling, who is working on the seventh and last book in the Harry Potter series.
"I don't want him to go over the Reichenbach Falls," King said in a reference to Arthur Conan Doyle's effort to kill off the character of fictional detective Sherlock Holmes.
Neither writer commented on Lindsay Lohan - but it's safe to assume they are, in fact, hoping for her demise.
Rowling said she was well into the process of writing the final book.
"I feel quite liberated," she said. "I can resolve the story now and it's fun in a way it wasn't before because finally I've reached my resolution, and I think some people will loathe it and some people will love it, but that's how it should be."