The governess is twenty and Bly is her first post. Miles and Flora are the loveliest children she has seen. The house has two towers and a lake, and the housekeeper, Mrs. Grose, cannot read. Miles has been sent home from school and nobody will say why. She has met her employer twice and thinks him splendid. She is never to write to him. One gray Sunday a man is at the dining-room window, his face at the glass. He wears no hat. Whoever he is here for, it is not her.
The Turn of the Screw is a ghost story in the governess's own hand, about two children she is certain only she can protect. It never says its worst thing outright. Its dread is made of what cannot be said to a child and what a child will not say back, and underneath it is about wanting to be the one who saves.
The Turn of the Screw is 42,845 words. At an average adult reading pace of 300 words a minute that is about 2 hr 23 min, or roughly 1 hr 47 min if you read quickly and 3 hr 34 min at a more deliberate 200 words a minute.
That count is measured from the complete public-domain text rather than estimated from a page count, so you can compare all the books side by side.