When Lucas talks to Marion about a play he saw in London, he is alluding to Patrick Hamilton's "Gaslight", which was twice made into a movie, by Thorold Dickinson in 1940, and by George Cukor in 1944.
Valentin wishes to makes a film entitled 'Angels of Mercy" (a story about nuns). This is similar to _Les Anges du Péché_ (1943) directed by Robert Bresson.