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Agent Invisible

noir detective in night time cityscape, illustration

Credit: Lukeruk / Shutterstock

"Don't ask questions. Get ready to run. Dupin's pinned a homicide on you."

Special Agent Dinah Carter and I had worked on only a couple of cases as partners in the FBI. Now she was programming me for survival mode, to elude the bureau's AI-based crime-solving system, Dupin.

"Lose your phone," Dinah told me. "You can be tracked. Avoid CCTV. Don't use ATMs or credit cards. Meet me at Del Floria's, the tailor on M Street Northwest, at five. Now go!"

Dupin had named me prime suspect in a crime that had occurred just moments before and miles away because I had guessed that the AI was fabricating evidence. I didn't realize then how soon I'd be declared dead.

I took the emergency stairs to street level, dropping my cell phone behind a fire hose. With my hood up and watching out for security cameras, I headed onto 10th Street Northwest. There's an ironic Internet café there, the love child of an Apple store and a high-end coffee shop. When I gave the barista cash for my half-hour online and thimbleful of espresso, he looked at me as if I was something he needed to wipe off his shoe. That left me with a dollar and some loose change.

I sat down at a screen and pulled out the AI Primer that Dinah had given me. In the back were the author's details—Professor Francesca Adriaco from Georgetown University. If I had any chance of surviving this, I needed her help. My message was short:

Hey Francesca—I'm Agent Saskia Lipcott from the FBI. I need to speak with you urgently about artificial intelligence.

I guess she had a system monitoring her emails; she replied in minutes and invited me to her office. I jogged all the way, in pain. If I ever survived this, I needed to exercise more.

"Hey, Saskia, good to meet you. What can I do for you?" Her Italian accent was cute.

"I'm new at the FBI," I said. "I read your AI Primer."

Francesca grinned. "A real page-turner."

"There's something I wondered about. If Dupin is so good at using the networks and security feeds to find people, is there any way to hide? Are there any loopholes?"

"I don't think the ACLU would call them loopholes, more opportunities for self-preservation."

"Whatever. I'm not trying to limit civil liberties. I'm not the man. I just want to understand the system."

The screen on an empty desk behind Francesca was broadcasting news. I wasn't really looking, but the banner caught my eye: "FBI agent killed." I tried to keep watching discreetly.

"Okay," said Francesca, pushing back her chair to a dangerous angle. "So, obviously you, uh, this person would need to avoid using any electronic equipment. Phones, laptops. Then there's security cameras… " She trailed off.

I couldn't keep up the pretense of listening. The scrolling text under the banner had filled in the name of the dead FBI agent. Saskia Lipcott. Me.

"You okay?" Francesca asked.

"Sorry, I'm easily distracted. You mentioned CCTV?"

"Right. Your person wanting to stay out of sight would have trouble with that. But Dupin has a limitation. AI recognition systems are easy to mislead if you know what you're doing. You just need appropriate imagery." Francesca opened her desk drawer and pulled out a couple of lapel pins. Instead of a flag or a logo, there was a small square with an abstract black-and-white pattern, like a crazy QR code.

"And these are?"

"Dupin's worst nightmare. AI systems don't see the way we do. A small change in an image screws up their recognition abilities. Put this pattern on your lapel and Dupin will think your head is a pumpkin."

"I'm sorry?"

"No, really. Now, if a human saw a person walking past with a pumpkin instead of a head, they'd be kind of suspicious. But remember, AI isn't general intelligence like we have. It's only good at one task. It sees a pumpkin walking past and dismisses that as a failed match."

"Can I take these?"

"Be my guest." As Francesca handed over the lapel pins, her phone rang. She held up a hand to me apologetically. "Yes? When was that? I see. No, well, she wouldn't if she's dead, would she? Certainly will." She hung up.

I had fixed one of the pins to my lapel and slipped the other into my pocket. "Is there a problem?"

Francesca hesitated. "No, I don't think so. Apparently, some rogue FBI agent was spotted in the lobby, asking for me. But now it seems she's dead. Strange, huh?" She opened another desk drawer and pulled out a basic cell phone.

I shrugged. "Weird."

Francesca nodded. "Take this phone. It's got my number programmed in. I got it for my mother and…long story. But I also think you ought to leave now, out the back. Just in case."

I didn't know what to say. "I… thank you."

"Go!" She smiled again.

I walked the streets until five, turning up at the old-fashioned tailor on M Northwest just as the shop was closing. They seemed to be expecting me—taking me to a grey back room that looked as if it was last decorated in the 1920s.

Dinah showed up a few minutes later. I didn't give her a chance to speak. "I'm dead?"

"Sorry," she said. "I didn't know what else to do. I thought it would give us some breathing space. I don't think Dupin suspects me yet."

"What now? Storm into the data center and destroy it?"

"That's not going to happen," Dinah said. "Dupin's too well protected. We need some way to discredit it…before there's a warrant out for me, too."

One of the staff from the shop came through and whispered something to Dinah. "Damn!" said Dinah. "Dupin knows I'm here."

"How? Your phone? Cameras?"

Dinah shook her head. "I left my phone three blocks away and avoided CCTV."

I pulled out the phone Francesca had given me and called her. She sounded pleased, but I interrupted. "Sorry, Francesca, there's no time. Is there any way Dupin could locate someone, even with the precautions we discussed?"

There was a long pause. Dinah was pulling at my sleeve. "We've gotta go."

"Does this person have contactless credit cards?" Francesca asked.

"Doesn't everyone?"

"It's just an idea; it's hard to prove anything with Dupin because machine learning has no transparency. I think it could use card readers in stores to detect RFID chips that pass close by unless they're protected. Screen your cards with metal. And if you happen to meet an agent Carter, you might like to tell her that she's now the main suspect in your murder."

"Thanks. Truly."

"Are we good?" Dinah asked me.

Before I could answer, two bulky guys burst into the room, brandishing badges. "Which of you is Dinah Carter?" said the bald one in the lead.

Dinah raised a hand.

"Dinah Carter, I am arresting you on suspicion of the murder of Saskia Lipcott. You."

I coughed loudly enough to disrupt his flow. "I think we need a word. My name's Saskia Lipcott."

For a moment, the look on his face was enough to distract me from wondering what the hell we could do now.

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Brian Clegg ( is a science writer based in the U.K. His most recent books are What Do You Think You Are?, exploring the science of what makes you you, and Quantum Computing, offering background to this new computing paradigm.

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