A Grenadier Guardsman who broke strict rules by dancing on parade outside Buckingham Palace is potentially facing a 21-day prison sentence and a 1000-pound fine.
Footage of the unnamed soldier performing a series of ballet-style pirouettes while on guard duty has become an internet sensation, watched by more than 1.7 million people on YouTube.
But Army top brass have reacted furiously to the video and are ready to hand down a custodial sentence.
The guardsman faces hours of marching practice and physical fitness tests at a military prison in Colchester, Essex. He also faces losing his wages for the period of his sentence - about 1,000 pounds.