Fringe type TV Show network Fox

John Noble has confronted and conquered an array of daunting acting challenges playing Fringe’s brain scrambled boundary-pushing physicist Walter Bishop. But when the star found himself literally brain scrambled as a result of an ongoing sleep disorder while shooting the first episode of the Fox drama’s fifth and final season, Noble had to ask for a time out.

“I couldn’t even think, mate,” the Australian actor tells EW. “I was working and going: ‘This is really hard.’” Which is saying a lot for a heady sci-fi series that routinely challenges its cast and audience with such noodle-cooking concepts as time travel, parallel worlds, and alternate timelines. With the blessing of producers and backers, Noble took 10 days off to seek treatment in Los Angeles. He’s now back at work in Vancouver, shooting the second episode of the season, which will launch as scheduled on September 28. “People were so bloody supportive, it was really touching,” says Noble. “I’m feeling more well rested now and sleeping better than I have in 20 years.”

Noble says that he’s suffered from a combination of insomnia and sleep apnea for years. After a busy summer of overseas travel and Fringe publicity (including a memorable, emotional appearance at Comic-Con last month), “I basically hit a wall, and we had to deal with it,” he says. “I went to the hospital, had all the tests, and we put the strategies into place to deal with both of those issues, including the space-age mask that I wear to bed now.” He laughs. “It’s pretty unsightly.”

Noble imagines that his addled alter-ego — prone to self-medicating with food, drugs, and other exotic substances — would have handled the situation much differently. “Walter probably would have just taken some LSD,” he says. “That really wasn’t an option for me.”

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