I've recently watched Lady Vanishes by Alfred Hitchcock. And I must admit- HITCHCOCK IS A GENIUS !!!
Hitchcock doesn't use any non-digetic music to create tension, he does not use low tone lighting, dark costumes and so on.
- uses humor- there were some funny elements in the film within what character said to each other. This made to movie more preasuable to watch.
- Camera work to create suspense: he gives audience information. this creates suspense because we see/know something that the character does not. For example a writing on a train window, which the characters didn't seem to notice.
- the plot itself is mysterious: train, old lady missing, no one seems to see her, main characters are looking for her.
here's a trailer, enjoy!