Most people tend to remember Robert Newton as Long John Silver, a role he perfected long after he gave up as an actor.
Jamaica Inn is an early film and here you see a fine looking Newton with the longest, darkest eyelashes I have ever seen on a man.
A side note: Not too long before Jamaica Inn was made, a scout for Sam Goldwyn spotted Newton in London and thought he would be perfect for the role of Heathcliff in the up-coming Wuthering Heights. Newton tested for the role and everyone but Goldwyn was thrilled. Goldwyn though Newton was "too ugly" to play Heathcliff, although everyone else thought he combined the emotional intensity and the black gypsy look that was perfect for that role. Eventually, Laurence Olivier was cast. He admitted that he always believed, his great friend, Newton would have been better, darker and more naturally dangerous as Heathcliff. I often wonder how Newton's career would have changed had he been given the role of Heathcliff.
Hitchcock takes advantage of the dual danger/kindness elements of Newton's personality to create a memorable hero. A young and lovely Maureen O'Hara is cast as the woman who comes to live with her Aunt after the death of her mother, only to discover she is in a den of cut-throats. She witnesses Newton being hung and just manages to save his life. Charles Laughton lends his special talent for seeming to one sort of person while actually being something quite different and Hitchcock rolls all these characters and a marvelous Leslie Banks, into a fine tumble of thievery and honor, love and loyalty, crime and punishment.
There are many of the familiar Hitchcock touches to move things along.
The climax is a bit over-the-top, but it affords Laughton a marvelous few moments.
Jamaica Inn has been re-made several times, but no one can replace Hitchcock, Newton, O'Hara and Banks.