The car shifts again. Anna manages to fill her lungs one last time before the air pocket disappears. She is on her knees on the back seat of the sinking car. The only escape route is through the windscreen, which is behind them. In order to reach it she will have to wrestle both Agnes and herself between the front seats, avoiding the crushed section of the roof.

It’s impossible. She lets go of Agnes and dives down to the side door. The car is full of water now, so the pressure ought to be the same inside and outside, which means she should be able to open the door. Theoretically.

She tugs at the handle, but it’s no use. The cold is shrinking her lungs, her movements are getting slower and slower. She braces her body against the driver’s seat and pushes the door as hard as she can with one foot.

Gradually it begins to open. White lights flicker in front of her eyes. Her heartbeat is deafening.

Three minutes, Håkan says again in that voice he sometimes used when they were training together. This is your last chance, Anna. Push, for God’s sake!

She gathers all her strength, opens her mouth and roars into the water, forcing the door centimetre by centimetre until there is a gap wide enough to get through.

She is out of oxygen, the white lights have turned into a multicoloured firework display, and yet somehow she manages to haul Agnes out of the car. She kicks against the bodywork, propelling them both upwards.

Keep going, Anna. Keep going, you can do this!

But Agnes’s lifeless body is dragging her down, and she is on the point of losing consciousness. On the point of being swallowed up by dark, ice-cold water, just like Simon Vidje. She closes her eyes and draws her daughter closer.

Suddenly, the pressure around her head eases, and she is above the surface. She gasps, takes breath after breath. The firework display comes to an end and her vision clears.

The shore is three to four metres away, and she tries to swim in that direction with one hand, keeping Agnes’s head above the water with the other. Her daughter’s face is ashen, her eyes closed. Blood is trickling from an ugly gash over her left eye.

Their progress is agonisingly slow. The current is forcing them back. Anna shifts her position so that she is swimming on her back with Agnes’s head between her hands, as she learned on a lifesaving course. It’s a little easier, and they edge towards the shore. Anna coughs and swallows river water, but the adrenaline pumping through her body enables her to keep going, in spite of the cold, the lack of oxygen and exhaustion.

Four minutes, Håkan whispers. You have to get ashore; you have to check her breathing.