I study the Beecher House, looking for some kind of ham radio tower. “Harriet Beecher Stowe talks about Sandusky in Uncle Tom’s Cabin. We had to read it in senior English class. You think she was related to Lucas Beecher?”

“A cousin.” Trey stares off into the distance. “Wouldn’t that be something?” he says, his voice tinged with wonder. “More than a hundred and fifty years later, and the Underground Railroad is still saving lives.”

“Guys, keep up,” Tanq says. “The guy on the radio said to go to the president’s park and look for a sign. Then he said we could just ‘follow the rail.’ So help me look for another sign. Something that would mark a trail.”

Trey nods, considering. “Another Underground Railroad marker?”

“Or,” I say, scanning our surroundings. “There! Another Null sign.” It’s smaller than the first, but still bright red. This time it’s splashed up against the concrete wall of a county building.

“Let’s go!” Tanq says, heading off, her new pack bouncing against her back. Emmaline scampers after, her tail furious with joy at going for a walk with her people, as if we’re in no danger at all.

We reach the second Null sign. Tanq puts a finger against it and gives it a swipe. “It hasn’t been here long,” she says, staring at her finger. “It’s not wet or anything, but it also hasn’t been here for months like some of the tags in downtown Columbus. This kind of paint cracks in the weather after a while.”

“Let’s look for another one,” Trey says.

“Don’t forget to keep an eye out for good cover,” I warn, noting the awning of the sandwich place across the street.

The breeze picks up, and I shiver. It’s been a cold, late spring, but I also wonder if I’ve been so cold because I was sick. Like my body doesn’t have the energy or even the flesh to keep me warm.

We find a symbol on the door of a brewery, another on a picnic table outside a bistro, yet another behind a sign advertising ferry rides. Then we’re stuck. No more symbols anywhere, no matter how hard we look.

“We must have missed one,” Tanq says. We’re standing beneath a redbud tree, staring out at an empty street. Sandusky is a ghost town now, quiet except for the whistling wind and the screaming of water birds. We’ve encountered fewer bodies than we did in Columbus. Maybe this far north it was just too cold to be outside when everyone started dying.

“Look,” says Trey, pointing to a nearby parking lot. Few cars remain in the lot, unrecognizable under a green-and-gray patina of bird droppings. Not from crows, for once, but rather a flock of seagulls, scrabbling about, occasionally fighting over a tidbit.

“Those gulls seem out of place, yeah?” I say.

“Not the gulls. The manhole.”

“Oh.”