Perhaps he had heard a noise outside. Or as a keen gardener himself wanted to check out the grounds. Whatever the reason, Prince Phillip was snapped taking a peek outside before the start of a state dinner in Bermuda.
The 88-year-old royal and the Queen - resplendent in a dusky pink ensemble, white gloves and tiara - were the guests of Bermuda Prime Minister Dr Ewart Brown and his wife Wanda Henton-Brown.
Their evening soiree was one of the highlights of the royal couple's short trip to celebrate the 400th anniversary of British settlement of the territory.
Earlier the Duke of Edinburgh looked amused when he was presented with a pair of Bermuda shorts - named after the island - by a man modelling a pair.
Businessman David Hamshere, who gave the Prince his gift, struck a quirky figure by teaming the bright red shorts with a suit jacket, shirt and tie.
He told the duke: "You'll definitely look very elegant in them."
A third of Bermuda's population - An estimated 20,000 people - lined the streets to give the couple a rock-star welcome, the likes of which have rarely been witnessed on the mid-Atlantic island.
It was said to be more than the crowd that welcomed the Queen on her last visit, almost 15 years ago.
Many say the large crowds were the result of a diplomatic spat earlier this year between Bermuda and the UK which raised questions over the island's sovereignty.