The most obvious candidate was echolocation.

Rad listened to him without uttering a word. By the dismissive look on her face as he wrapped up, he knew she wasn’t buying any of it. She dug a cigarette from the silver case in her clutch and lit it with a quick, flustered motion. “Is this why you never told me what you do on your boat every day, Marty? Because you’re hunting mermaids?”

“I told you I’m a marine biologist and a zoologist, and I’m mapping the ocean with sonar, all of which is true. But yes, I believe mermaids and mermen exist—the non-binary preferred plural form is ‘merfolk’—and yes, they’re the object of my search.”

“Umm, now I’m not following,” said Jacky. “Rad, you don’t know who Marty is?”

“Who he is? You’re talking like he’s famous or something… You’re not famous, are you, Marty?”

“I was on a TV documentary,” he said uncomfortably. “But I don’t think we need to get into that right now—”

Jacky said, “He’s The Merdoc, for crying out loud!”

“The Merdoc?” Rad looked like she’d been slapped. “You mean…from that Netflix show?”

“You know of it?” Marty said, surprised. “I figured since you never recognized me, you never watched the documentary.”

“I didn’t watch it, but of course I know of it. Who doesn’t? It was huge. Especially after… Oh, Marty.” Sympathy, or perhaps pity, filled her eyes.

Marty knew what she had been about to say: Especially after it was discovered to be a gigantic hoax.

Rad now had her phone out, her thumbs tapping rapidly. “Dr. Martin Murdoch. Murdoch. That’s why you never told me your last name. You knew I’d learn who you were.” She stared at Marty. “What the hell? What the hell, Marty? Why didn’t you ever tell me any of this? What was the big secret?”

“I haven’t told anybody this, Rad. Not since coming to Sri Lanka. The documentary’s not something I’m proud of.”

Rad said, “You knew, Jacky. You knew Marty was The Merdoc?”

Jacky nodded. “However, Marty never told me. I recognized him at a science conference. My gig at the Daily Mirror is general news and current affairs. I covered the Netflix documentary’s fallout. I could have picked Marty out of a hundred-person lineup.”

“Well, this is…a trip, isn’t it? I think I want to slap you, Marty. But…” She stared at him again with that disconcerting who-are-you look. “Whatever. I don’t care. You’re The Merdoc, okay. Jesus Christ, okay. And you think that skull in that video belongs to a mermaid?”

The mention of the skull got Marty’s blood racing. He felt as though he were a child, and it was six a.m. on Christmas morning. Even so, he did his best to temper this excitement. He wasn’t going to be taken for a sucker again. The skull could be a fake, part of another hoax, or someone’s sick joke. He said, “I’m not going on the record saying anything until—”

“You’re not on the record, Marty! It’s just us, okay? I’m not going to call up TMZ, okay?”