Gerard banged his knee on a radiator as momentum sprawled him and the chair across a little desk.

‘It’s just a stopper,’ Georgia said, hoping her deliberate calm would rub off on the guys as she held a grubby net curtain out of the way. ‘If we take this out, the window will slide all the way.’

Georgia grabbed a screwdriver but strained to loosen the screw. Zac took over. The first head loosened easily, but he had a fight with the second.

Gerard’s phone rang.

‘Slide it now,’ he ordered.

But the window stopped in the same spot.

Georgia looked up. ‘There’s one in the upper rail as well.’

Zac swore as he moved back in with the screwdriver. ‘I can’t reach. Pull the table out.’

Georgia carefully dragged away a glass-topped table, on which the drone sat, ready to launch.

‘That was Kamila,’ Gerard announced. ‘She’s outside the construction site. The PM is on stage, about to start his speech.’

‘Come on,’ Georgia urged.

Zac was at full stretch, making it hard to apply strength. The first screw dropped out of the window casing and pinged off a metal radiator. More in hope than expectation, Zac dug the head of the screwdriver under the bung and twisted. The plastic snapped away, but the screw head stayed in place.

‘It might clear,’ Zac said.

Georgia gave the window a hard shove. The upper frame screeched against the jutting screw, but she got a waft of fresh air as the window opened a full metre.

‘Rock and roll!’ Zac grinned.

‘We have no idea how long this speech will be,’ Gerard said urgently as he helped Zac push the drone table back to the window.

‘Hold those billowing curtains out of my way,’ Georgia ordered. She fitted her FPV goggles, then said sarcastically to Gerard, ‘Power on now, maybe?’

Zac held the curtains as Gerard activated power switches for the drone and impeller.

‘Good to launch,’ Gerard said.

Georgia’s world was now through goggles. The display showed full power packs, two cameras recording and the impeller online. She throttled up aggressively, knowing the anti-collision system would save her from the ceiling, then tilted to fly forward.

Gerard had calculated the journey from City Lodge’s ninth floor to the podium where the PM was speaking as 783 metres. From a standing start to a top speed of 90kph, the flight would take forty-three seconds.

Georgia was used to launching from the ground and felt disorientated having eight storeys below as she settled into level flight. As the drone accelerated, Georgia skimmed close to glazed office facades, making the drone harder to spot than against open sky.

She hadn’t counted on two men in a window-washer’s carriage and skimmed their heads.

‘They’re all dressed in black,’ Zac said, watching on the laptop.

‘Protection officers,’ Gerard confirmed. ‘Snipers, most likely.’