Prince Charles in his tuxedo looks anxiously ahead as a protester's fist pounds on his car. His wife Camilla's mouth gapes in shock above her emerald dress.
These are the dramatic images captured by an Associated Press photographer as student protesters vented their anger on the most elite, and supposedly well-protected, of targets -- a car containing the heir to the British throne and his consort, the Duchess of Cornwall.
The couple were heading to a theater for a charity variety performance Thursday when their Rolls Royce crossed paths with a volatile gang of demonstrators who attacked the vehicle with fists, boots and bottles -- and chanted "Off with their heads!"
Young, excited and angry, the protesters had broken off from a large student rally and were running through London's West End, bent on spreading mayhem among the throngs of pre-Christmas shoppers.
They broke a Starbucks window, overturned a couple of postcard stands -- but seemed as surprised as the royals were when they came face to face.
Adnan Nazir, a 23-year-old podiatrist who was following the protesters, was among the first to recognize the royal couple in their customized Rolls Royce with its extra-large windows.
"I said, 'It's Camilla!' I wasn't trying to alert them. I was just surprised to see her," he said. "A few people turned around and started hitting the windows. People started kicking the car."
The attackers, up to 20 of them, surrounded the limousine and pounded it with fists and bottles, smashing a window, and splashed the gleaming car with paint amid chants of "Off with their heads" and "Tory scum."
The car behind, an official royal Jaguar, also came under attack,
In the confusion, Nazir said, a window opened. Charles kept his calm, gently pushing his wife toward the floor to get her out of the line of fire.
"Charles got her on the floor and put his hands on her," Nazir said.
The 62-year-old prince remained calm, "waving and giving the thumbs' up."
"It was just a surreal thing," Nazir said. "It was completely manic."
After several chaotic minutes, the car managed to force its way through the crowd and drive off.
Charles' office, Clarence House, said the couple was unharmed. But Camilla, 63, looked shaken and Charles was somber as the couple arrived at the London Palladium a few minutes after the attack.
Ever the professionals, they soon managed smiles as they met performers including Kylie Minogue and the boy band Take That.
Prime Minister David Cameron called the attack "shocking and regrettable" -- and police will have to answer questions about a security breach that brought an angry mob within touching distance of the future king and his wife.