Paul Bettany says an intense scene on the set of Marvel’s VisionQuest left him with 10 burst blood vessels in his eye. The actor described the incident during an appearance on Jimmy Kimmel Live! on Oct. 29, saying it happened while he pretended to have a device on his head affecting his brain.

“I was just wildly overacting,” Bettany recalled. He said he strained so much that the blood vessels in his eye burst, calling it a lesson that “less is more.” Kimmel showed a photo of Bettany’s bloodshot left eye from the set and joked that the actor could make his eye appear injured on command.

The injury took about two weeks to heal, while filming continued. Bettany reprises his role as Vision in the series, which was filmed in England and also features James Spader, Ruaridh Mollica and Emily Hampshire.

Bettany also said the production involved a heavy workload, with so many pages to cover each day that he often worked on scenes at night and found it difficult to unwind. He called the experience of returning to the character amazing, nearly two decades after joining the Marvel franchise as J.A.R.V.I.S. in 2008’s Iron Man.

Sources: E! News.