The Secret Adversary
"The Secret Adversary" was the second Christie work to be turned into a film. Made in Germany by the "Orplid Film" company, it was released in that country on 15 February 1929 as "Die Abenteurer G.m.b.H.", a silent movie which ran for 76 minutes. It was released in the UK and US under the title "Adventures Inc." Character names from the book were changed for the film. Previously thought to be lost, it was given a rare showing at the National Film Theatre on 15 July 2001 (see National Film Theatre: A Tribute to the Work of Agatha Christie)