He still corresponded with Henry VIII, but nevertheless signed in 1546 the act cancelling the marriage and peace treaty, and on 10 September 1547 commanded the van in the great defeat of Scotland at Pinkie, when he again won fame. Early in October 1547, Angus tried to recapture the island of Inchcolm from the English with five ships. However, he kept up a secret correspondence with Andrew Dudley, the English commander at Broughty Castle, and wrote that he had made excuses to Regent Arran and prevented his retainers from joining the siege of Broughty.