I can’t sleep so I head down to B deck where the Believers like to party.

Folks who believe in UFOs no longer subscribe to the idea of aliens zipping around the flatlands and deserts of the American southwest. For alien chasers, the ocean is where it’s at. Why wouldn’t alien craft hit our oceans? They can zip down through the water, hiding from radar, and dig into the ocean floor for their minerals or to lay their eggs for a future infestation or whatever they’re here for, and there’s hardly any chance of bystanders calling in a sighting. Some believe aliens have always been under there, possibly for millions of years, and when a UFO enters our airspace it does so not from above, but from below.

The Believers are a cruise line’s best customers. They board cruise after cruise hoping to get lucky and encounter an alien craft while enjoying a mojito in the comfort of a deck chair. They’re also a lot of fun to be around.

“Cap’n,” a man with a thick, gray beard says as he hands me a caipirinha. We’ve met before.

“Good to see you again, Jimmy.”

He looks like he might lean in for a hug. My posture dissuades him.

“Any signs?” I ask.

A woman in a print sundress and a permanent smile at the wondrousness of it all tells me the dolphins are extra loud tonight.

“That means they’re on the move,” she says. “When the visitors break through the ocean floor and navigate the waters, the dolphins can’t shut up about it.”

Several of them are dancing. A fat man who might be as young as 30, but whose ocean tan has given him a face like the trunk of a redwood, holds his hand out to me with mock elegance. “Captain, may I have this dance?”

“I prefer to sit this one out,” I say. “My doubt will throw off your rhythm.”

“Skeptic! Banish her!” he shouts through a big, drunken smile. Then he takes the hand of a blonde woman who was already spinning by her lonesome, and the two of them twirl sloppily to the pop songs pumping out of someone’s cell phone speaker.

The Believers try to summon the aliens with joy. They present themselves as being as far from a threat as possible, hoping to throw a party to which aliens can’t help but crave an invitation. This is why it’s so fun to hang out with them on my cruises. They tend to be counted on for an after-party following whatever tamer events might have been on offer during more reasonable hours. And they’re up all night, ready to go drink for drink with you for as long as you can stay awake.

I plop down in a deck chair with Jimmy on my left, and on my right, Madison, a sad woman in her 40s with gorgeous brown hair who’s also been a passenger under my command several times before.

“Hello, Heather,” she says to me. “What’s on your mind?”

Madison claims she was abducted in 1998. There was a flash of red light, followed by a four-month-stretch of lost time, no memories. She’s been hunting for her abductors ever since.

“I met my half-brother for the first time,” I tell her. “He’s here on the boat. One of the last times me and my dad talked, he told me I had a brother. I never thought I’d actually meet him.”

Madison asks if I’ve spoken to my brother about our dad. I shake my head no.

We watch the Believers dance with wilder movements, less predictable spins and twists. The more reserved dancers return to their seats until soon it’s just the blonde woman. She seems to be accepting a spirit into her body.

“What will you do if you encounter your aliens?” I ask Madison.

“Ask them to take me with them, duh,” she says. “What would you do if you encountered your father?”

If he wasn’t already dead, I’d kill him, but I don’t say that since it’s not right for a ship’s captain to talk patricide with her passengers.

The blonde woman is screaming now. This happens. They get a flash memory of the alien experiments that were conducted on them and they fall to the deck wailing like they can feel the probes then and there. I take it as my cue to finish my drink and head back to bed.