“You don’t need to come over, Gregor. I can bring my violin, play it for all of you. I’ll bring it tomorrow, yes?”

He gave her a long look. “I suppose.”

She stopped then, blinking to cover the widening of her eyes, pulling him in for a second hug as she tried not to show her reaction, her skin prickling all over, events slowing with her breath as every single hair on her body stood up. Despite the heat in the apartment, she felt suddenly ice-cold, and her jaw clenched.

I have never played him that piece. How does he know it? There was only one possibility. He was spying on her. There were listening devices, and maybe even cameras, over in Ruby’s flat too.

It was important that Gregor thought she was still in love with him, only denying herself because of Constance and Leonie. So it was useful now that the fear looked so much like desire. Standing there with her pupils dilating, her tongue wetting her lips, trembling, she must have looked to him like a fruit ripe for the picking.

They had to get out, and soon. Tonight they would act. As she’d watched him disappear into the stairwell, she’d known they would need to search fast. If she and Constance were going to access his private space without him knowing, it had to be after he’d set off in the car and before he arrived at wherever he was headed, because he couldn’t be watching them and driving at the same time. They didn’t know how far he was going or, therefore, how long they had. The moment his car started to move, she’d given the thumbs-up to Constance, who stuck a piece of masking tape over the tiny camera lens in the light fitting so that Ruby could pick the lock without it being recorded.

They checked all around the door for traps and wires, but could find nothing, not even the telltale borehole of a hidden camera.

“I think it’s safe.”

Ruby walked into Gregor’s scrupulously neat and clean bedroom, flipping the light switch as she went. The bed was covered in a white cotton top sheet, folded back to reveal a white cotton duvet. Crisp white pillows were perfectly symmetrical. There was a white chest of drawers and a matching wardrobe. The painted walls were bare. Ruby got a feeling of blank nothingness. Like a hotel room, but with even less character.

Having been reluctant to enter the room, Constance suddenly pushed past her and flung open the wardrobe doors. She shoved aside the shirts, dragged the bottom drawer open.

“It’s not in here,” she said. “It has to be somewhere. Where’s he hidden it?”