whodunwhat

plural whodunwhats

1. A whodunit in which the nature of the crime is a mystery, as well as the identity of the perpetrator.

   Our narrator reads, rereads, and slowly realizes that ulterior "plots" are afoot; a whodunit develops into several whodunwhats; a murder may or may not have happened, or is yet to happen.

   1997, Rain Taxi, volumes 2-4, page 27

   2 more examples

   In Sleuth Anthony Shaffer created the whodunwhat, where not only the identity of the criminal but the nature of the crime — indeed, the reality and reliability of everything we've seen with our own eyes — is part of the mystery.

   1993, Contemporary Dramatists, page 592

   "It's not a whodunit — it's a whodunwhat," says Cris Barrish, a local reporter. And few foresaw that Capano's brothers Louis, 47, and Gerard, 36, squeezed by prosecutors and threatened with jail time, would turn on Capano in court […]

   1999, Time, volume 153, numbers 1-7, page 124