Are they making it all up? The short answer is, “Yes.” The longer answer is, “Yes, but…”
While every moment of Whose Line is improvised, it is also highly adapted for television. What this means is, for every 22 minutes you see, hours of video has been recorded. If a scene is going south, they can stop tape and start again from the beginning. They record enough material for several shows at one time; if you want to see this in action, watch the show on the CW’s web site and watch who is on the show, what they are wearing, and especially who is sitting behind the host. You will soon be able to tell which shows came from the same taping.
Also go to YouTube and search for “Whose Line Bloopers”. You will see many (so many) incidents of the producer or network censor interrupting scenes and telling the stars they can’t use certain suggestions because of…reasons. It’s interesting to see the inner workings of the show. It’s particularly interesting to see how much this irritates Ryan Stiles.
Most, if not all, of the stars of Whose Line also do live improv shows; Colin and Brad tour nationally, for example, and others perform around the world. They are talented improvisers who can hold their own on live stages or in front of the cameras, and yes, every bit of it is made up.
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