I crashed to the floor as Mackenzie slammed me from behind and collapsed on top of me.

“What are you doing?” I shouted at her as we scrambled to our feet.

Mackenzie didn’t need to say a word. The tables had turned. Shauna had the icy arrow to Katrina’s throat.

I hugged Mackenzie. We were saved! Shauna to the rescue like in some old-time Western. Yeehaw! I wasn’t going to be skewered by Cupid’s arrow like the worst Valentine’s Day shish kebab ever.

“Thanks, Shauna,” I said and raised my hand for a high-five from my new hero. But she left me hanging.

A small stream of blood was dribbling down Katrina’s neck where the ice arrow was digging into her skin. Yeah, I knew she was a killer but … “Hey, Shauna, let’s take Katrina to the lodge. The boys are rounding up everyone. You’ve caught the killer.”

As soon as I said it, I understood that I was dead wrong. The scene in front of me shifted. It was like one of those trick pictures where you see different things based on how you looked at it. I had been so focused on Katrina that I didn’t see the other picture. I finally saw Shauna – not the super-perky event-planner that she wanted me to see. I finally saw the scary woman she’d been hiding all along. In a split second, she’d switched from superhero to evil mastermind.

“You killed Lucinda,” I said and wished for the millionth time that I could switch off the blurt mechanism that always got me in trouble. Not every thought that popped into my head should fly out of my mouth – and this one could get us killed. Shauna smiled this weird wild smile.

“Why?” Mackenzie asked, shocked by this hairpin turn of events. “You orchestrated this entire weekend. You invited these people here. You misdirected us every chance you got.”

When she said it like that, how did we not realize it before now? Shauna had become our friend. She was always there working behind the scenes. Mackenzie grabbed the back of my snowsuit and tugged me out of Shauna’s reach.

“Leave!” Shauna screamed at us, spittle flying from her mouth.

“We can’t do that,” I said. “We can’t let you kill anyone else.”

“You may have saved Alexia and Blake, but you’re not going to save Katrina!” Shauna shouted. “She’s going to get what she deserves.”

“Please help me,” Katrina begged between sobs. “She’s Serena Coleman.”

“Shut up!” Shauna smacked Katrina to the ground and held her down with her boot. In the weeks we’d spent with her, I’d never ever seen a hint of the anger that was exploding from Shauna now. How could I have been so blind?

“Serena?” Mackenzie’s voice trembled.

“I used to be Serena until they killed me,” Shauna said. “I received a scholarship to that horrible school. I thought that it was my chance for a better life.” She cackled in this sort of scary way. “Tell them. Tell them what you did to my best friend.”

“Parker,” I said.

She pointed the arrow at me. “How do you know that name?”

“Katrina wrote a story about a girl named Parker who accidentally drowned,” I said.

“Accident!” Shauna laughed again. “Alexia, Blake and Katrina made our lives hell. One night they kidnapped us from our beds, covered us in paint and then launched us into the lake.”

“We didn’t know Parker couldn’t swim,” Katrina sobbed. “I’m so sorry. We never meant to hurt anyone.”

“You bullied me and Parker all the time,” Shauna shouted and pressed her foot deeper into Katrina’s chest. Katrina screamed in pain.

I needed to say something to stop her, but Mackenzie thought of something first. “This won’t bring Parker back.”

“I know, I just don’t think that Katrina deserves to keep on living.” Shauna grabbed the hood of Katrina’s snowsuit and dragged her towards the front door. “Now it’s Katrina’s turn to take a swim in an icy lake. With any luck, they won’t discover her body until spring and by then I’ll be long gone.”

“Why did you kill Lucinda?” I asked because I needed her to stop moving, and I wanted to know why.

“We were kids,” Shauna said. “But she was the adult. She withdrew my scholarship and paid everyone to keep what her granddaughter did a secret. No one believed me. She ruined my life.”

“Your life isn’t ruined,” Mackenzie said.

“Yeah,” I agreed. “You are great at what you do. You planned this whole weekend…” I stopped when I realized that her life probably was ruined now that she’d killed someone.

“Lucinda wasn’t supposed to die like that,” Shauna said. “I’d lost twenty-five kilos, dyed my hair and even changed my accent, but Lucinda recognized Serena Coleman. I agreed to meet her at the ice hotel while everyone was watching the Northern Lights. I pushed her. She cracked her head on the unfinished ice bed. I covered her with water. I made up the story about her staying at the cabin. I had Lucinda’s phone so I even texted Alexia to buy some time.”

“Let Katrina go, and I’m sure we can tell the police about your…” What was that phrase that meant she’d done what she’d done because of the bad things that had happened to her?

“Extenuating circumstances,” Mackenzie filled in the right words.

“I don’t want to hurt you,” Shauna said. “I wanted to scare you in the maze. I would never hurt the two of you.” Her expression changed from full-on crazy to seriously sad. “You remind me so much of me and Parker. You are two opposites that together make this perfect team. You are very lucky to have each other.”

Mackenzie and I looked at each other. We were lucky. I hoped our luck held.

“Forget you ever saw me with Katrina,” she said. “You can’t leave me,” Katrina begged.

Mackenzie and I held our ground. We weren’t going anywhere.

“If you won’t do it for me,” Shauna said, the cold, scary look was back in her eyes, “then do it for Ariadne.”

“What?!” Mackenzie and I said in unison.

“What have you done to my grandma?” I shouted and took a step closer to her. Mackenzie restrained me.

“She figured it out,” Shauna said. “Well, not the why part, but she knew I was the one who had orchestrate this whole deadly weekend.”

“You didn’t…” I couldn’t say the horrible end of that sentence. I hoped Grandma wasn’t another accident like Lucinda.

“No, but if you don’t find her quickly, she will die.” Shauna pulled Katrina kicking and screaming past us. “You’ve got a choice to make. Try to stop me and your grandma dies because I will never tell you where she is. Or let me walk out that door and I’ll tell you everything.”

What else could we do? I raised my hands in surrender. I had no intention of letting Shauna hurt Katrina, but we had to play along.

“Chase!” Mackenzie said and stared at me wide-eyed. “We can’t stand by and let Shauna kill Katrina.”

Shauna pushed open the door. While she was distracted, I winked at Mackenzie. “I have to save my grandma.”

We followed Shauna out into the snow. Mackenzie’s hands were also held high in surrender. Shauna threw the ice arrow aside and reached into the pocket of her snowsuit. “Ariadne’s in the Northern Lights cabin. I tied her up and built a fire, but that was hours ago. If that fire goes out…” Shauna tossed a set of keys in a nearby snow pile.

“If that fire goes out…” I lunged at Shauna, but Mackenzie tightened her grip. A sob caught in my throat. My sixty-nine-year-old grandma wouldn’t survive long in an ice-cold cabin.

“Duck,” Mackenzie whispered in my ear and yanked me to the ground.

Snowballs whizzed by from every direction, pelting Shauna again and again until she was beaten to the ground.

It took me a moment to see through the blur of snow that a semi-circle of Winter Wonder Resort guests and staff surrounded us.

I dived for the keys while Mackenzie rushed to the now staggering Katrina, who collapsed in Mackenzie’s arms.

I pulled off my gloves and dug through the snow like some crazed mole. My stiffened, nearly frozen fingers finally closed around the keys. I rammed the keys and my hands deep into my snowsuit pockets.

“We thought you might need a little backup,” Toby said as he raced over to me. “We heard Shauna’s crazy talk and the only weapon we had was the snow – and lots of pensioners! Taylor and I always keep a stash of snowballs ready, we just didn’t know we’d use them to catch a killer.”

I hugged Toby. “Thanks.” I couldn’t waste any more time. “Send help to the Northern Lights cabin.” I tore off towards the line of snowmobiles.

I hopped on the closest one, strapped on a helmet and goggles and revved the engine.

“You aren’t going without me!” Mackenzie shouted, snatching up a helmet and goggles. She flung herself on the back of my vehicle. I pointed the snowmobile in the direction of the cabin.

As we sped away, I hoped we weren’t too late to save Grandma. Being my grandma was dangerous; I prayed it wasn’t deadly.