Cruise ship passenger who fell overboard swam with sharks for 20 hours

In what sounds like most people's living nightmare, a cruise ship passenger fell overboard and swam with sharks for 20 hours.

US man James Michael Grimes had been enjoying his time on a Carnival cruise ship with his family on the evening before Thanksgiving (23 November) when disaster struck.

You can watch a segment of his shocking account below:

The 28-year-old spoke with Good Morning America about his experience, saying that one of his fears superseded the others.

While he faced all sorts of threats while stuck in the ocean treading water, from jelly fish to rip currents and, of course, the sharks that lurked below, one of the things that kept him going was his fear of drowning.

But that's only part of the story.

Discussing what it was like after falling off the Carnival Valor vessel, he told the outlet that he went to use the toilet at around 11pm that night and doesn't remember much after that.

"The next thing I know, I regained consciousness. I was in the water with no boat in sight," he said.

And if that doesn't keep you up at night I don't know what will.

But rather than panic, Grimes looked up at the stars and the moon above him and decided he wanted to survive.

Good Morning America/ABC

"I felt like I was given a chance right then... you're alive for a reason... that [fall] could've killed me, but I felt like from that moment on, I was trying to stay positive," he continued.

"And, you know when you're here, you're still alive for a reason. So, all you got to do now is swim and survive. I was hoping they will start looking for me, they will find me eventually," Grimes said.

That being said, it was far from being an easy wait for Grimes. At one point, a large sea creature came up to him 'real quick' and bumped him in the leg, so he kicked it before it could get a chance to latch on.

"It scared me not knowing what it was or how big it was – all I could see was a fin," he said.

To deal with his hunger, he resorted to eating what he could find – a floating stick that he believed to be bamboo.

Grimes said that his religious faith and his family kept him going through that dark period of time.

"I wanted to see my family and I was dead set on making it out of there," he recalled.

"I was never accepting that this is it, this is going to be the end of my life. I'm 28 years old. I'm too young. This is not going to be it.

"I always thought there's a greater purpose for my life. Now, I know for sure I'm meant to do something on this Earth."

He continued: "It was just the Lord was out there helping me, giving me strength and helping me stay afloat."

Good Morning America/ABC

After noticing Grimes was missing, his family alerted the cruise staff who then notified the US Coast Guard. By this point, he had already been in the water for a whopping 12 hours.

Amazingly, they found him 20 hours after he had fallen overboard – and even now they're not entirely sure how he managed to fall.

Carnival Valor explained that they do have safety barriers which ensure people don't fall overboard, which was backed by the US Coast Guard.

In a statement shared with ABC News, the Coast Guard said: "We greatly appreciate the efforts of all, most especially the US Coast Guard and the mariner who spotted the guest in the water.

"Cruise ships have safety barriers in all public areas that are regulated by US Coast Guard standards that prevent a guest from falling off. Guests should never ever climb up on the rails."