Answer:
The Mousetrap is the longest running show in the world. The Mousetrap is a murder mystery play written by Agatha Christie. The theatrical show opened in the West End of London in 1952, and has been running continuously since then. As of 2012 it has entered its 60th year.
It has the longest initial run of any play in history, with over 24,500 performances. It is the longest running show of any type of the modern era. The play is also known for its twist ending, which at the end of every performance the audience is asked not to reveal.
Next Question: Which is world's longest running TV variety show?
Previous Question: Which actor married the niece of a US President?