Theo remained reserved for the first half hour, then handed over the spaceship’s roof.

Preston helped attach the windows while Eli explained the mission to Neptune.

At lunch, Theo said, ‘I thought you weren’t coming again.’

Preston set down his sandwich.

‘I know you were worried.

I can’t promise there will never be a delay, but I can promise I won’t disappear without telling you what happened.

And I’ll keep trying.’

Theo thought about it and nodded.