It was pretty bold of me to run down the hallway of a stranger’s apartment, but I didn’t think twice about it.

“Hey, Alec?” I called. “It’s cool. Let’s talk about it.”

I pushed open his bedroom door and poked my head in, only to see that things were definitely not cool.

The window leading out to the fire escape was open. I caught a quick glimpse of Alec’s sneakered feet as he climbed up the ladder outside.

Headed for the roof.

“Hey!” I shouted, and ran straight for the window.

It didn’t seem safe for a little kid to be crawling around on a fire escape. It didn’t seem all that safe for me either. But I crawled right out the window and looked up to see Alec stepping off the steel structure and onto the roof.

“Alec!” I called. I don’t know why. It wasn’t as though he was going to stop and come back just because I yelled his name.

I climbed up after him, and when I’d gotten halfway up, I heard the window slam shut below me. I looked down and saw Mrs. Swenor inside, pulling on it, trying to get it open. For some reason the window had slid shut and was now stuck.

I was on my own.

I quickly climbed up, trying not to think about how this was the very same roof that Michael Swenor had fallen from. When I got to the top, I saw Alec running to the far side.

“Alec, stop!” I yelled.

“You can’t have it!” he shouted back.

I climbed onto the roof and walked after him. I didn’t want to panic the kid. I was up there to make sure he didn’t get hurt, not to run him off the roof.

Oh yeah, and to get the key.

As I strode across the tar-papered surface, the wind picked up. A dark line of storm clouds was creeping in from the west. No biggie. We wouldn’t be up here long enough to get caught in the rain.

Alec reached the far side and turned to face me. Tears ran down his cheeks.

“It’s okay,” I said, trying to sound calm. “My name’s Marcus. Your father knew my father and—”

“I know who you are,” Alec said, sobbing. “You can’t have the key.”

He clutched the brass key and folded his arms together.

The wind grew stronger. The line of storm clouds drew closer. Fast. Really fast. Suddenly, the roof was cast into shadow. I looked over my shoulder and saw another line of dark clouds looming in from the exact opposite direction. Huh? There were two lines of ominous black clouds racing toward each other.

“I’m sorry about your dad, Alec,” I said. “I hear he was a really good guy.”

His tears came even harder.

“He followed me up here to save me,” Alec cried.

“Tell me what happened.”

“The dog. It was under my bed. It chased me here, to the edge. Right here. I saw a ladder, but when I climbed over, it wasn’t there anymore. It was a…a…”

“An illusion,” I said with a growing sense of dread. I didn’t like where this was going for all sorts of reasons.

Alec nodded. He was spewing impossible facts…that I knew were totally possible.

“It was the lady,” he said, sobbing. “She tried to make me fall.”

I stopped breathing.

“Lady?” I asked, stunned. “What lady?”

“An old lady,” he said. “With long gray hair.”

It felt as though I’d been punched in the stomach.

“In a green dress?” I asked, incredulous.

Alec nodded. “Nobody believes me.”

I didn’t know whether to cry or scream or puke or all three. What happened to Michael Swenor wasn’t an accident. Or a suicide.

It was her.

“I believe you,” I said numbly.

“She is very bad.”

“Yeah, I’m getting that.”

“My daddy saved me,” Alec said through hitching breaths. “But then the dog came back. It knocked him over the side.”

The stiff wind picked up and began to howl. I had to plant my feet wider apart, or I might have been blown off the roof. Alec crouched down and pushed himself against the low safety wall for protection.

“That key belonged to my father,” I said. “Your dad wanted me to have it.”

“No!” Alec cried. “It was my father’s!”

Lightning flashed through the clouds, followed by a sharp clap of thunder. The two storm fronts had collided, blocking out every last bit of blue sky. The dense, dark canopy had turned day into night.

I knelt down a few feet from Alec.

“Let’s go downstairs and talk about it,” I said, trying to sound calm, but it wasn’t easy while screaming to be heard over the howling wind.

“No!” he yelled. “I’m keeping it forever and—”

He spotted something over my shoulder, and his eyes went wide.

“No, not again,” he said, so low I could barely hear it.

I spun around to see what he was looking at.

A woman stood on the far side of the roof.

Not Mrs. Swenor.

Her.

The old woman’s long green dress and black shawl snapped in the wind. Her gray hair was no longer piled on top of her head. Long, loose tendrils flew around her head in a swirling maelstrom that looked like gray fire.

It made my blood run cold.

“Is that her?” I yelled to Alec.

Alec managed to nod.

I stood up to face the woman.

“Who are you?” I yelled. “What do you want?”

She didn’t move. Good thing. If she’d taken a step closer, I think I would have passed out.

“She wants the key,” Alec called to me. “I won’t let her have it either.”

“Did you hear that?” I called to her. “You aren’t getting the key.”

A brilliant bolt of lightning tore through the sky, followed by a huge rumble of thunder. It was as if my announcement had angered the gods.

We couldn’t stay on this roof forever, but the only way down was to go past that old creep. It was a standoff. Both of us were waiting for the other to blink.

I saw movement along the edge of the safety wall behind the old lady. At first I thought it was a shadow, but there was no sunlight to make one. A dark mass rose up and crept over the edge of the roof.

“What is that?” Alec asked nervously.

It looked like thick, molten tar. It oozed up over the edge of the safety wall and slid down until it hit the surface of the roof. From there it kept moving and growing. It stretched out for several yards along the roof behind the old lady while flowing forward, spreading toward us. When it reached the woman, it split and skirted around her as if it could think and knew she was there. It then joined back together in front of her, leaving the old lady on a clean, dry island.

Either the nasty blob had a mind of its own, or she was controlling it.

Alec scrambled to my side and leaned into me for security.

I wished I had somebody to lean into.

“I’m scared,” he said.

Join the club.

The dark pool now covered half the roof and continued to spread forward, moving ever closer to us.

I looked back over the edge of the roof behind us, desperate to find a way to escape.

This time I saw it.

There was a metal ladder attached to the side of the building.

“There’s a ladder,” I said to Alec. “I’ll go down first. You follow right behind me.”

“No!” he screamed. “It’s not real.”

In my growing panic I’d forgotten about the illusions.

The old lady smiled at me as if she knew how close I’d come to going over the edge. She lifted up her hand and opened her palm in a gesture that meant only one thing.

Surrender the key.

The wind howled as the black ooze grew closer. What was it? Would it burn us? Was it a black hole that would suck us into a bottomless pit? Or would it catch our feet in its stickiness and drag us over the edge?

“Maybe we should give it to her,” Alec said with fear.

Thunder rumbled as lightning ripped through the clouds.

The woman stood with her hand outstretched, unwavering.

The ooze was only a few yards from us and flowing closer with each passing second. I looked back to the ladder.

It wasn’t there anymore. It had never been there. It was an illusion.

Knowing that actually gave me an idea.

“I think we’re okay!” I shouted to Alec. “None of this is real.”

“Are you sure?” he asked tentatively.

No, I wasn’t. But it wasn’t as though I had another plan. I stood up straight and called out to the old lady, “You’re not getting the key.”

It was a huge risk. Giving her the key would probably save us. But did we really need to be saved?

“Here,” Alec said.

He held the key out to me. It dangled from the leather cord the same way as when his father had held it out to me. His ghost father.

“Better you have it than her,” he added.

A twisted bolt of lightning blasted through the sky, followed by a gut-rumbling clap of thunder.

I looked to the old woman and saw something new.

Her expression had changed.

She looked angry.

The black ooze was only a few feet from us. A putrid rotten-egg smell wafted from it and stuck in the back of my throat, making me gag. The wind blew even harder. If it got any stronger, we wouldn’t have to worry about the black ick anymore. We’d be blown over the edge.

Alec clutched the leather cord in his small fist. The key on the other end was swept up by the wind, pulling the cord parallel to the roof.

I gave one last look at the old woman.

“No way,” I said defiantly. “This belonged to my father.”

I reached out and grabbed the key.

“Now it’s mine.”

It felt warm in my hand, as if being there was absolutely right.

The woman didn’t agree. She threw her head back and let out an unearthly bellow that sounded like a mixture of pain and anger so powerful that it made the roof tremble.

“Look!” Alec exclaimed, pointing to the sky.

The clouds were breaking up, allowing sunshine to peek through.

The wind died quickly, its shrieking faded to silence.

The rooftop was slowly bathed in warm golden light from above.

More important, the black pool was gone.

So was the old lady.

“Alec!” called Mrs. Swenor as she climbed up onto the roof.

Alec ran to meet his mom. She dropped to her knees as he slammed into her, nearly knocking her over. The two hugged as if neither would ever let go.

“I couldn’t open the window,” she cried, the tears flowing. “What were you thinking? Why did you come up here?”

“I was thinking about Daddy,” Alec said with confidence. “This was the last place I was with him. I thought maybe he’d tell me what to do.”

“Never, ever come up here again, do you understand?” she scolded.

“I won’t have to,” Alec said. “I gave the key to Marcus. I think it’s where it belongs now.”

The two looked up at me.

I felt the weight of the large key in my hand.

“I don’t know what that key is,” Mrs. Swenor said, “or why it’s so important. But your father wanted Michael to give it to you, so now it’s yours.”

“Thank you” was all I could think to say.

“Promise me one thing?” she asked.

“What’s that?”

“Be very, very careful.”