He was served by Ramona Giorgetti in the seafront cafe. She said: "He had his hat down over his face and you could hardly see it was him. I bent down to have a look and he smiled and realised it was David Tennant. I was like - oh my God - and ran back and told all the staff.
"He asked for a double cone - Strawberry and Vanilla. He was looking at all the different flavours and I told him I would give him a minute, and then my Dad Luigi served him the ice cream. His Dad apparently used to live in Kames Bay so I think he was visiting for a bit of nostalgia.
"One of my friends saw him coming over on the ferry. He was a lovely guy and really nice and smiley."
At around 3.30pm, the Casanova actor was seen departing the Millport ferry and walking up Largs Main Street. He was spotted by Nardinis at the Moorings employee David Purdon who said: "Just saw the best Doctor Who ever walking up the road."