On Jimmy Kimmel Live!, Gyllenhaal talked about jumping trains with the English band on their 2011 Railroad Revival Tour of the Southwest with Edward Sharpe and the Magnetic Zeroes. The tour, which had them riding a vintage train around America, was chronicled in the GRAMMY-award winning documentary, Big Easy Express.

Gyllenhaal explained that he's been friends with the guys in Mumford and Sons for years, way before they got famous. "I have a lot of close friends from England," he said. "I'm not sure why that happened, but it did."

After seeing the band play in San Pedro, California, Marcus Mumford told him he should get on train with them and head to Arizona. Gyllenhaal wasn't so sure about it, admitting that he told Marcus he couldn't go because he didn't have an extra pair of contact lenses.

Luckily, he didn't let his bad eyesight get in the way and jumped on the train. He ended up staying on tour with them for two weeks and had his mom Fed-Ex him his contact lenses.