She squeezes her eyes tight shut a couple of times and steadies herself. Realises she can breathe. A dwindling pocket of air has formed, and she fills her lungs. Her eyes become accustomed to the darkness, and she can just make out something beside her. She fumbles with her right hand, finds the release button for the passenger seat belt. She presses it, tries to grab hold of Lisa and feels a hand on hers. She drags the young woman up towards the air pocket, which already seems much smaller. She hears a splutter, then a cough.

‘The door . . .’ Lisa gasps. ‘I can’t open it.’

‘The windscreen,’ Anna says. ‘You need to dive down and get out through the windscreen.’ She is already on her way to Agnes, managing to force her way between the front seats. She takes another deep breath and dives towards the place where she last saw her daughter. She gropes around, finds a leg and thumps it hard with her fist.

Agnes doesn’t move. Anna raises her head again. The air pocket is down to a few centimetres now, and she can feel the pressure on her eardrums as the rising water takes its toll. She dives again. It’s as if a band of ice is tightening around her temples as she searches desperately for the seatbelt. How long has Agnes been underwater? A minute at least. Probably two.

Three minutes, Håkan informs her, managing to sound both matter-of-fact and worried. You have three minutes. Not much more.

She finds the button and presses it, but nothing happens. She tugs at the belt, using so much oxygen that she has to go back up for air. She takes a breath, tries to slow her heart rate. Dives again. Her fingers are freezing cold, she can’t get a grip on the belt. Her efforts make the car begin to tilt forwards.

Calm, Håkan says. Try to keep calm.

Suddenly, the belt comes free. She pushes it away from Agnes’s lifeless body and pulls her daughter close. Manages to drag her up towards the roof. The air pocket is so tiny now that she has to tilt her head to the side in order to reach it. She lifts Agnes’s nose and mouth above the surface of the water.

‘Agnes!’ she shouts. ‘Wake up, Agnes!’

No reaction. The car tips and the air pocket moves, finds the highest point inside the vehicle, just above the rear window. She tries to drag Agnes to the right spot, pushes her up towards the roof.

‘Agnes!’ Slaps her across the forehead. Still no reaction. She takes a huge breath, presses her mouth to Agnes’s and blows. She hears bubbling in Agnes’s throat. She must have swallowed water; it might even be in her lungs.

You have to get out, Håkan says firmly. Right now!