At last he continues. “We had to get rid of her. Only thing I could think of was to take her up to the glacier and find a crevasse. Do you remember her massive snowboard bag?”

I hear Curtis’s sharp intake of breath.

Her blue Salomon wheelie bag. I can picture it exactly. Saskia brought it up the mountain sometimes when she needed to take more than one board up. People often took snowboard bags up there, especially when there was a comp. It’s useful to have a spare board in case you damage one. We used to leave stuff lying around all over the place and I never had anything stolen.

“We squeezed her into it,” Brent says.

A strangled sound bursts out of Curtis.

Brent continues. “It had wheels but it was heavy and I’d need help with doors and stuff, so I made Heather come with me. In the bubble, Heather was losing it. Reckoned she saw the bag move.”

Again that strange sound from Curtis. He doubles over, head in his hands.

Words tumble out of Brent like he’s rushing to get the story out before he breaks down completely. “There was a skier in the bubble with us. I told Heather to shut up, she was just seeing things. We reached the glacier. Hardly anyone was up there, they were all at the pipe getting ready for the comp, so we dragged the bag off to a quiet spot. I was going to open it and check if she was alive, but before I had a chance, you came jogging across looking for her, Curtis.”

Curtis moans and clasps his head. His gloved fingers grip his hair so tightly I’m surprised he’s not pulling it out. He mentioned seeing his sister’s stuff. He must be thinking how close he came to finding her.

How he may even then have had a chance to save her.

“We didn’t want you to see the bag, so we ran over to you.” Brent hesitates. “You were pretty angry.”

So far this is matching up with what Heather told me. Maybe she was telling the truth after all. When I find her, I’m going to bloody kill her. Did Curtis actually say that?

“Heather panicked,” Brent says, “and told you Saskia went in the building a minute ago, so we went inside with you to pretend to help you look. We only left the bag for ten minutes, I swear, but when I went back for it, it was gone.”

Brent slumps, as though all the life has now left him.

My heart is in my mouth. Is Saskia dead or not? Maybe she was still alive but unconscious as they took her up the lift. Then, as they reached the top, she slowly came around. I picture her opening the zip, crawling out of the bag. And sneaking away . . . where?

“It was me.” Curtis’s words are muffled.