Jennifer Aniston and Justin Theroux spent their honeymoon at the Four Seasons resort in Bora Bora, but it wasn't as relaxing as it sounds.

According to Theroux, who appeared on Friday's Live With Kelly and Michael, he got pretty spooked when a scuba diving expedition didn't go as planned. The 44-year-old newlywed agreed to take some diving classes offered during his honeymoon and his first trip out into the ocean went off without a hitch.

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But when he decided to go out a second day with some friends, things didn't go as planned when he was given a French diving instructor that, who he says, didn't understand English very well. Theroux told cohosts Kelly Ripa and Michael Strahan that he went down "pretty deep" and noticed that his oxygen tank was in the red. When he motioned to his instructor that he was running out of air, he says he was told it was fine and to keep swimming.

Continuing to see that he was "really deep in the red," Theroux motioned again to his instructor that he wanted to go up. "I was using every hand signal I could possibly figure out," he said.

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The story gets even crazier. Theroux attempted to sign to his friend what was going on and, through eye communication, he recalled that his pal thought the actor was about to die. Theroux said that the instructor then gave him an emergency respirator that sent "bubbles everywhere and water down my throat."

"Now, I'm like coughing and panicking," he recalled. "It's not a great feeling."

Theroux said he started to think that someone was out to get him. "Your brain goes into a crazy place," he said, adding that he thought, "Oh my God, this is some plot to kill me."

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Aniston's new husband said he was furious when he got back to the boat, and hasn't been scuba diving since.

Talk about trouble in paradise!

The traumatizing experience hasn't stopped Theroux from trying new things, though. This week, he joined Instagram, and has already managed to change Throwback Thursday to Theroux-back Thursday.

The Leftovers star proved to be a fast learner of social media as his second Instagram post ever was a flashback pic of himself at 16 years old. Theroux looks oh-so '80s in the image, donning several earrings and bracelets, along with long sideburns and a bomber jacket.

Aniston also participated in TBT, thanks to Mayim Bialik."Yes this is me and Jennifer Aniston in my childhood bedroom," the Big Bang Theory star captioned the vintage pic. "We did a show together before I did Blossom. #tbt"

Even all those years ago, Theroux and Aniston would have made a cute couple. Here is ET's inside look into the A-list couple's luxurious honeymoon: