In 1998, the television show “Whose Line Is It Anyway?” debuted on ABC with a bespectacled Drew Carey as its affable host. The premise was simple: Performers created characters, scenes and songs based on audience suggestions and cues from Carey, introducing viewers to improv comedy with a series of sidesplitting segments. Cast members Colin Mochrie and Brad Sherwood pick up where the show left off with their Two Man Group tour. Anchored by the seasoned comedians’ chemistry, the hilarious romp relies entirely on audience prompts. While the material changes nightly, one thing remains constant: Anything goes.