Queen Elizabeth is the epitome of the mantra "keep calm and carry on" but, early in her marriage to Prince Philip, she apparently lost her cool and threw her shoes at her husband in anger.

The shocking revelation is underscored in a new book about the Duke of Edinburgh. Biographer Ingrid Seward wrote Prince Philip Revealed, which detailed what happened between Queen Elizabeth and her husband during their royal tour of Australia in 1954.

According to reports, the royal couple had been enjoying a weekend off when camera crews caught Prince Philip storming out of their chalet. What followed next surprised the staff because Queen Elizabeth's tennis shoes came flying and she also threw a tennis racket at her husband.

Queen Elizabeth then shouted at Prince Philip to return to their chalet. She allegedly held his arm and dragged her husband inside and then she saw the people's shocked faces.

The biographer said that the royal press secretary gave a warning to those who witnessed the quarrel between the royal couple. He said that they will face arrest if they squealed on what they've witnessed.

The camera crew recording the royal tour was also asked to surrender their film. Queen Elizabeth later thanked the crew and apologized for her outburst, Seward wrote.

It will not be the first time Queen Elizabeth and Prince Philip would have their epic public squabbles despite their discreetness. Married for the last 73 years, Seward said that a "tough" Prince Philip was frustrating to deal with but a Queen who likes to talk in riddles can also grate on the nerves of her husband.

Seward, who is the editor for Majesty magazine, said that she's had personal encounters with the Duke of Edinburgh quite a few times as a royal journalist. She described these encounters as "extremely brusque" because that was the nature of the man the Queen married.

However, the royal also had a charming and interesting way about him that appealed to members of the press. There were actually members of the press who were assigned to cover the Duke of Edinburgh just to report on his gaffes and mischiefs.

Prince Philip has accepted early on that his role in life would always be to walk two steps behind the monarch. However, the Duke of Edinburgh remains a complex character who has high standards and strong inner strength that may sometimes overshadow Queen Elizabeth.

Clashes between the royal couple, especially in their young marriage, were inevitable. However, their union had been steadfast because Prince Philip was devoted to his wife despite his other flaws.