The Captain America: The First Avenger star flew to Namibia in 2008 with Sir Ian McKellen, Ruth Wilson and Jamie Campbell Bower to film the series, which was adapted from the original 1960s show starring Patrick McGoohan.
However, Atwell has revealed the shoot descended into chaos as the writers changed the script every few days, and the production turned into a paid holiday for the cast after the first director was fired.
She tells British newspaper The Times, "(It was) a joke. They re-wrote it as they went along. Within the two weeks, the first director was fired and all the actors got together and went on safari. We went quad biking with Ian McKellen - it was heaven."
The remake aired in America in 2009 to scathing reviews.