It's the craze that's sweeping the nation, and now even actors and crew on hit medical drama Holby City are getting in on it.
The calm scene of people hanging outside the Holby City set chatting in medical uniforms soon erupts into chaos.
A Templar Knight is seen in the foreground riding a giraffe, while everyone jumps around like they are in need of medical treatment.
Check out the video above to experience the full madness.