‘Refresh it,’ Pip said impatiently. ‘If he doesn’t turn left, then he’s not heading to Amersham.’

The refresh button spun with fading lines. Loading. Loading. It refreshed and the orange avatar disappeared.

‘Where’s it gone?’ said Pip.

Ravi scrolled around the map to see where Elliot had jumped to.

‘Stop.’ Pip spotted it. ‘There. He’s heading north up the A413.’

They gazed at each other.

‘He’s not going to Amersham,’ Ravi said.

‘No, he is not.’

Their eyes followed for the next eleven minutes as Elliot drove up the road, jumping incrementally whenever Ravi pressed his thumb on the refresh arrow.

‘He’s near Wendover,’ Ravi said and then, seeing Pip’s face, ‘What?’

‘The Wards used to live in Wendover before they moved to a bigger house in Kilton. Before we met them.’

‘He’s turned,’ Ravi said and Pip leaned in again. ‘Down somewhere called Mill End Road.’

Pip watched the orange dot motionless on the white pixel road. ‘Refresh,’ she said.

‘I am,’ said Ravi, ‘it’s stuck.’ He pressed refresh again; the loading spool spun for a second and stopped, leaving the orange dot in the same place. He pressed it again and it still didn’t move.

‘He’s stopped,’ Pip said, clutching Ravi’s wrist and turning it to get a better look at the map. She stood up, grabbed Ravi’s laptop from her desk and settled it on her lap. ‘Let’s see where he is.’

She opened the browser and pulled up Google Maps. She searched forMill End Road, Wendoverand clicked on to the satellite mode.

‘How far down the road would you say he is? Here?’ she pointed at the screen.

‘I’d say a bit more to the left.’

‘OK.’ Pip dropped the little orange man on to the road and the street view popped up.

The narrow country road was enclosed by trees and tall shrubbery that glittered in the sun as Pip clicked and dragged the screen to get a full view. The houses were just on one side, set back a little from the road.

‘You think he’s at this house?’ She pointed at a small brick house with a white garage door, barely visible behind the trees and telephone pole that bordered it.

‘Hmm . . .’ Ravi looked from his phone to his laptop screen. ‘It’s either that one or the one to the left of it.’

Pip looked up the street numbers. ‘So he’s either at number forty-two or forty-four.’

‘Is that where they used to live?’ Ravi asked. Pip didn’t know. She shrugged, and he said, ‘But you can find out from Cara?’

‘Yes,’ she said. ‘I’ve had a lot of practise with pretending and lies.’ Her gut churned and her throat tightened. ‘She’s my best friend and this is going to destroy her. It’s going to destroy everyone, everything.’

Ravi slipped his hand into hers. ‘It’s nearly over, Pip,’ he said.

‘It’s over now,’ she said. ‘We need to go there tonight and see what Elliot’s hiding. Andie could be alive in there.’

‘That’s just a guess.’

‘This whole thing has been guesswork.’ She took her hand away so she could hold her aching head. ‘I need this to be over.’

‘OK,’ Ravi said gently. ‘We are going to end this. But not tonight. Tomorrow. You find out from Cara which address he’s going to, if it’s their old house. And after you finish school tomorrow, we can go there at night, when Elliot’s not there, and see what he’s up to. Or we call the police with an anonymous tip and send them to that address, OK? But not now, Pip. You can’t upend your whole life tonight, I won’t let you. I won’t let you throw away Cambridge. Right now, you are going to study for your exam and you are going to get some bloody sleep. OK?’