As it turns out, Deadliest Catch didn’t get its name by accident. The high-stakes reality TV show follows the brave crews of several fishing boats as they set out on harrowing voyages to do one of the most dangerous jobs known to man: harvesting crabs. Their missions are sometimes even deadly (hence the name) with entire vessels sinking and causing unimaginable loss.

However, on rare occasions, the beloved stars of the show occasionally face obstacles that have nothing to do with their jobs — and on the Sept. 24 episode of the show, the F/V Wizard‘s Captain Keith suffered a mysterious medical emergency that has fans seriously worried about his health.

Here’s what we know.

Fan-favorite Deadliest Catch captain Keith Colburn gave fans a scare on a recent episode of the show. Following an intense and emotional argument with his brother, Monte, which ensued after Monte’s decision to sail west of St. Paul resulted in empty crab pots and a loss of around $30,000 in fuel, Keith suffered a sudden medical emergency.

Without warning, Captain Keith collapsed offscreen, unresponsive as Monte yelled out to him. The camera showed the man lying on the floor face-down, and additional crew members rushed to the scene to try and help.

Keith then proceeded to gag and cough, unable to get up from the floor. The terrifying moment lingered until the end of the episode, leaving viewers to worry about the captain’s declining health.

Speculation online ensued after the airing of the episode, with many theorizing that Captain Keith may have suffered a stroke.

On Reddit, one user queried their fellow fans: “Y’all think Keith had a stroke? When they mentioned his arm going numb … Seemed like maybe a stroke. Either that or a severe heart attack again. Either way … pretty scary.”

Others have speculated that it could have been some sort of panic attack induced by the argument with his brother.

“I’m going with a severe panic attack which made him fall, striking his head,” another Reddit user posited. “He was worked up and probably had a vasovagal response, causing him to fall to the floor. Secondary to that, he struck his head on the way down.”

Another said, “Told my wife multiple times this season he’s going to stroke out. Simple argument with his brother had his heart racing.”

Captain Keith, who is in his sixties, has suffered health issues in the past, including a previous heart attack and even a bacterial infection that forced him to temporarily step away from the reality show in Season 14. Earlier this year, rumors even spread that Keith would be retiring from Deadliest Catch — and crabbing altogether — but he quickly denied them, staying, “You can’t take that away from me right now.”

Now, though, this his recent medical emergency has brought with it a whole new host of questions, most of which will hopefully be answered during the Oct. 1 episode of the show.