In 2012, to celebrate the 30th anniversary of Channel 4, a strand of programmes were shown known as Channel 4 Mash-Up. The usual presenters of programmes were swapped with those from other programmes. 8 Out of 10 Cats does Countdown began as a one off special as part of this strand and was popular enough to become its own series.
2012[]
2012–present[]
Australia | Belgium | Croatia | Denmark | France | Greece | Israel | Italy | Macedonia | Netherlands | Serbia | South Africa | Spain | Sweden | Turkey | United Kingdom (Celebrity, 8 Out of 10 Cats does Countdown) | USA
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