‘Because I know who you are,’ I blurt. ‘You taught me the Spreebogen Variation, there’s only one person who’s ever used that move. I know you’re Commander Steiner.’

‘Who?’ Granddad looks up at me.

‘Commander Steiner. A commander in the Stasi. Look, it says here.’ I reach into my pocket and show Granddad my phone. ‘See!’

Granddad fumbles for his glasses but his hands are shaking so much he can hardly find his nose. I wish I hadn’t started this. He might be a Stasi commander, but he’s my granddad and I don’t want to upset him any more than I have.

I start to pull my hand away.

‘No.’ Granddad grips my arm tightly and squints at the screen. I hold my breath as he reads the headline out loud.

‘Youngest ever schools chess champion wins using moves of Stasi commander . . . What?!’ Granddad pulls the screen closer. ‘Felix Schopp beat off strong challengers from schools all over the country using the Spreebogen Variation of the Yugoslav Attack, a move only ever used by the former East German secret police commander Lionel Steiner.’

Granddad leans forward. ‘Commander Steiner,’ he whispers. ‘I never thought I’d have to say his name again. I . . . I . . .’

My heart beats as fast as a rabbit’s. I wish I could take it back, but it’s too late now.

‘I’m sorry, Granddad,’ I say. ‘I didn’t want to believe it, but you mentioned the Spreebogen when you told me about your sister, and I saw his name on the cards in your wardrobe—’

‘No. It is wrong!’ Granddad snaps. ‘It is wrong! This is wrong!’ He jabs his finger at the screen. ‘This is not what happened. He stole my move! Steiner stole the Spreebogen Variation from me.’

Final Curtain

Bump.

Knock.

Bump.

Thud. Thud. Thud.

Bump.

Knock.

Thud. Thud. Thud.

These are the noises coming through the ceiling. Granddad told me he needed some time on his own, that he needed to think, but he’s been in his bedroom so long that I really think he must be packing a suitcase to go back to Germany.

I walk over to the window and peer out between the curtains. Two girls I don’t know are doing handstands by our tree, Mum and Dad are unpacking things they bought at the car boot sale and Jake’s riding round the square on his bike. He wants me to go out, but Granddad was so upset when I told him about Commander Steiner that I don’t want to leave him alone.

Bump.

Knock.

Thud. Thud. Thud.

I look up and follow Granddad’s footsteps across the ceiling.

Click.

Knock.

Thud. Thud. Thud.

I walk back towards the sofa just in time to see Granddad’s hand gripping the banister as he walks down the stairs. I want to believe he’s not the commander, but why would he be leaving if he wasn’t?