She presumed Longhorn had done it out of guilt. The baby was his, Mel had told him, threatened to tell his wife, he’d panicked and strangled her, left her in the bushes. When it all came out and his wife knew, he couldn’t take it.

Emilia Longhorn had backed him on the doorstep, claimed he was the victim of a stalker, but she changed her tune later. Maybe her confidence in him was blown out of the water by Mel’s body turning up, or the news of the pregnancy. Hannah was getting ahead of herself, they hadn’t confirmed the baby was Peter’s. She tried phoning Thomas at the station but he wasn’t there. She needed to know the baby was Peter’s. If it wasn’t, that was more dark matter and dark energy lurking in the shadows.

She reached the house and stood at the front gate staring at the address. ‘0 Greenhill Gardens’ was so weird, like the house didn’t exist, more dark matter. She wondered if there was another world somewhere in the multiverse where all the house numbers were negative, where the sun sucked energy from the purple skies, and where Mel was still alive, in her room right now studying for exams, staring out of the window and wishing she was out in the Meadows at a barbecue.

Hannah could hear drumming from the top floor of the house, a syncopated beat floating through the tree branches across Bruntsfield Links. She imagined Gran up there, hunched over, drumsticks a blur, eyes closed as she leaned in to the rhythm. Drumming was both maths and magic at the same time.

As a little kid, Hannah loved watching Dorothy play, eyes wide from the noise, amazed at the skill involved. When she’d tried it herself, it was clear some things weren’t passed down through the generations. She was scared to hit the drums, even more so the cymbals, unwilling to give herself up to this bigger thing. She thought now maybe that was a mistake, maybe giving yourself over to bigger things than yourself was the way to live. Was that 222what Mel did, dared to get out there and connect with the universe in a more direct way? Or was she just caught up in the dragnet of everyday lust and desire, the messiness of people and their emotions? Was she trying to set herself free from society’s bullshit?

Hannah felt exhausted by the grief and sadness, there seemed to be no release from it. She spotted Schrödinger eyeing up some sparrows on a bird feeder hanging from a pine branch. He was motionless in the shadows, eyes following the flutter of wings. She walked to the house close to the birds so that they flapped into the high branches away from the cat.

Indy was on her hands and knees in front of the desk, fiddling with cables, skirt stretched tight across her bum.