Of all of JB Priestleys work, and there is a lot of it, the most well known is this play. I myself have been drawn back to it repeatedly since I studied it in school. It deals with an intrusion by a mysterious Inspector to the family life of the Birlings who are having a dinner party for their prospective son in law and daughter.
The crux of the play is that all the characters have, by degrees, contributed to the suicide of one Eva Smith. It is a clever idea and shows JBs view that we are all part of society and all must look after each other.
A good version of the play can be found here. But I do find the actors a little bit too posh for the “pulled myself up by my bootstraps” Birlings. I would love to hear your comments below.