Considering I have not read the book, I found the storyline very original and well acted too. I loved Charles Laughton as Sir Humphrey Pengallan. He was the perfect villain/double agent because I disliked him to no other but was still willing to give him a second chance (and don't ask me why).
My only complaint about this classic was the quality of the film, mostly with the sound. The octave went up and down like a merry-go-round. Although this could have something to do with the fact that it was on Instant Netflix. Despite this small complaint, Jamaica Inn was a very enjoyable film.