The slab behind him was doing precisely that and it was almost fully closed.

Rastor fired another grenade up at the skyscraper and it rocked again . . .

. . . and with the crunching sound of breaking stone, the great upside-down tower began to peel away from the ceiling.

Rastor grinned.

There was no stopping it now.

The skyscraper would fall.

His work here was done.

It was time to go. He had to get out before the slab in the exit doorway closed completely.

He also didn’t want to be anywhere near the obelisk bridge when the skyscraper fell—it might take the whole damn bridge with it.

He nodded to his men—seven grey-masked Serbian commandos—and they all hustled out through the exit, under the lowering slab of stone.

Lily and Easton arrived at the bridge at a sprint and raced out onto it, dashing between its high stone obelisks.

Each of the obelisks was huge, easily forty feet tall, and they ran in pairs down the length of the bridge, creating a striking avenue.

Lily and Easton came to the jagged void in the bridge’s middle. Two obelisks stood at its edge like posts for a missing gate.

Lily bit her lip in thought. ‘Easton, you got any grenades on you?’

Easton pulled one from his belt and handed it to her.

‘Step back,’ she said as she lay the grenade at the base of the left-hand obelisk, pulled the pin and stepped back.

Bang!

A short sharp blast detonated at the bottom of the giant obelisk, blowing a chunk of stone out of it, and . . .

. . . the obelisk toppled toward the void.

And Easton realised what Lily’s plan was: she was trying to use the fallen obelisk to create a bridge across the gap.

He was smiling at her ingenuity when the obelisk slammed down against the opposite edge of the broken bridge.

Only it fell slightly askew—not perfectly across the void—and to Easton’s horror it teetered on the opposite edge for a moment before it rolled off and dropped away into the abyss.

‘Damn it!’ Lily shouted.

‘Lily!’ a voice called and she spun to see Jack, Zoe and Smiley running at full speed off the spiralling path onto the obelisk bridge.

‘What’s going on!’ Jack called.

‘Kinda busy here!’ she shouted back. ‘Easton, quick, have you got another grenade?’

Easton did. He handed it to her.

Lily dashed over to the remaining right-hand obelisk, set the grenade at its base and pulled its pin.

This was their last chance.

If this obelisk didn’t fall and land cleanly across the void, they had no way to get across it.

It was all or nothing now.

Bang!

The grenade detonated. The obelisk fell . . .

. . . and slammed into place across the gap, so that it now lay horizontally across the void like a fallen tree across a creek bed.

‘Let’s go.’ Lily danced across the fallen obelisk, high above the abyss.