The Harry Potter star and his wife Shane are keen boaters, and took their barge from Cardiff in Wales to Clydebank, Scotland for upcoming BBC4 series Timothy Spall: Back At Sea.

But the adventure was marred by gale-force winds, leaving them stranded in the same spot for hours on end.

Spall tells Britain's The Sun, ""It was blowing a Force 5 gale and the boat was thrown around like a rag doll.

""We were going at five knots but the wind was coming at us at five knots in the opposite direction so for a while we were going nowhere! It was the worst voyage of our lives. This is when the elements remind you that they are the boss.""

The show will debut in the U.K. later this month (Aug11).