John Boyne 
The Boy in the Striped Pyjamas (NHB Modern Plays) 

Bruno has a friend called Shmuel. Like Bruno, Shmuel is nine years old. Their birthdays are on the same day. But Shmuel lives on the other side of a fence, and he's always wearing striped pyjamas…
Based on the best-selling novel by John Boyne, The Boy in the Striped Pyjamas is a heart-wrenching tale of an unlikely friendship between two innocent boys. Angus Jackson's deeply affecting adaptation was produced by The Children's Touring Partnership and Chichester Festival Theatre on a UK tour in 2015.
'Heart-breaking… A marvelous piece of theatre' – The Public Reviews
'Parents and teachers looking for a good way of introducing children to the horrors of the holocaust will find what they need in this adaptation of John Boyne's multimillion-selling novel' – The Times