It is time for something exciting, interesting, challenging, risky, etc. to begin. "It's showtime," he murmured, as he entered the ring for the boxing match. OK, guys, it's showtime! Let's show the world just how powerful our new device is!
See also: showtime
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
exclam. (It’s) time to start! (Said of beginning anything exciting or challenging.) Are you ready for action? Okay. It’s showtime!
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.