On the surface, Kate McCue has been making waves as the first American female to become captain of a cruise ship, in this case, a $1-billion, 143-ton behemoth called Celebrity Edge, designed to carry 2,900 passengers.

Below the surface, though, the good captain is something else. Every now and then, she'll wriggle into a tail fin and plunge the waters where her vessel is stationed to lead an undersea life as a mermaid.

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First American woman to commandeer a cruise ship

McCue's been a captain since 2015, when she was hired by Celebrity Cruises to helm the cruise ship Celebrity Summit and later on the Celebrity Equinox, before being offered her current gig, which also happens to be the company flagship.

It's a job she's wanted ever since her family took her on a cruise when she was 12. After pursuing studies at California State University Maritime Academy, she started running banana boats in the Caribbean, before getting a toehold into the cruise ship industry, where she worked her way up the ranks.

She denies experiencing any instances of discrimination however, by being quick to point out that most of a cruise ship's staff is comprised of minorities anyway, a benefit of being surrounded by diversity.

Being a mermaid is a hobby

But she certainly receives added scrutiny as a mermaid, which she calls a hobby and an infatuation ever since she saw the movie The Little Mermaid, still one of her favorite flicks. In costume and a diver's mask, she's capable of plunging to depths of 40 feet.

On one occasion, she swam close to another cruise ship and by the time she got back to Celebrity Edge, rumors were floating around about several mermaid sightings.

She's a Celebrity Cruise ship celebrity in her own right

Celebrity Cruises, fully realizing they had a celebrity within their ranks, have not only used her in commercials and other promotions, but they also handed her a rather historic gig. On March 8, International Women's Day, she'll still be in charge of Celebrity Edge, but this time refitted with an all-female crew.

Her celebrity status extends online with more than 115,000 followers on Instagram, while her traveling companion, a cat that answers to Bug Naked, has an account with nearly 36,000 followers.

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