Dangerous Corner

One of J.B. Priestley's time plays, it was first performed in 1932 at the Lyric Theatre.  

A chance remark in the conversation after dinner leads to an investigation of the death of Martin Caplan by his brother.  Did Martin really kill himself, and why?  Or was he murdered?

In an intriguing plot where all the characters have at least one dark secret to hide, this play has the ingredients of a really good 'whoddunnit'.  Then just when all is revealed, Priestley twists the plot just once more.