They build a comedy empire with Empire's GRACE BYERS making a guest star appearance. Hosted by comedian Aisha Tyler, cast members Ryan Stiles, Wayne Brady and Colin Mochrie, along with guest comedian BRAD SHERWOOD, put their comedic skills to the test through a series of spontaneous improv games that are prompted only by random ideas supplied by the studio audience. The four performers must use the little information they have and their wild imaginations to conjure up hilarious characters, scenes and songs out of thin air. After each round of improvisation, Aisha will dole out points to our four performers and declare a winner at the end of every episode. But, as everyone knows, on Whose Line, "Everything is made up and the points don't matter."