Mark Williams attended the Harry Potter and the Half-Blood Prince Premiere held at the Odeon Leicester Square on July 7 in London.
The 50-year-old actor, who playes Arthur Weasley in the Harry Potter films, fell over and went flying on the slippery carpet at the rainy Premiere.
Daniel Radcliffe, who stars as Harry Potter, and Rupert Grint, who plays Ron Weasley, also got soaked by the rain.
Daniel Radcliffe (Harry Potter) looked wet at the Harry Potter London Premiere
Rupert Grint (Ron Weasley) got drenched at the Harry Potter London Premiere