Читать книгу The Courier - Ava McCarthy - Страница 6

Beth fidgeted behind her. ‘What now?’

‘If we had more time, we could lift Garvin’s prints from around the house.’ Harry wrinkled her nose. ‘Maybe make some kind of mould. Problem is, with ten fingers to choose from, it’s a bit hit and miss. We only get three shots before the vault locks us out for good.’

Beth groaned. ‘We’ve only twenty minutes left.’

Harry peered at the recessed opening. ‘When did your husband last open the vault?’

‘This morning. Why?’

‘Has anyone touched the finger sensor since?’

‘Not that I know of.’

Harry fetched her torch and shone it into the recess. The beam picked out a faint smudge of grease on the metal pad. She snapped off the light and ran through her options. She could hack the sensor in a few different ways, but the priority here was speed.

‘What are you going to do?’ Beth said.

Harry shrugged. ‘Use the only fingerprint we have. The one on the sensor.’ She saw Beth’s blank look and explained. ‘I’m going to try and reactivate it.’

Harry bent down low so that her mouth was on a level with the metal pad. It was a capacitive sensor that measured electrical changes across its surface when a human finger touched it. A high measurement meant a ridge in a fingerprint, and a low measurement meant a valley. The sensor put it all together to reconstruct a fingerprint pattern.

The trick now was to make it think that Garvin’s finger was still there.

Harry swallowed, and licked her lips. She needed to breathe on the surface of the sensor, letting the moisture from her breath gather between the lines in the grease stain. With luck, it’d be enough for the sensor to measure the capacitance and mistake it for an actual finger.

Gently, she breathed on to the surface of the pad, exhaling for three or four seconds. The screen beeped, and she glanced up at the message: