It’s 1984, and 13-year-old Tim is sitting on the school roof, waiting for the world to end.

Or at least for it to start making sense.

His life used to make sense. It was made up of two things: the exciting new world of home computers, and worries about nuclear war.

There were certainly no girls in it.

But then he met Penny, who’s into pop music, and somehow manages to be optimistic about life, despite having a very difficult mother. (Difficult, as in, she sometimes throws roof tiles at people.) For the first time since the death of his own...