While "Jamaica Run" has got a few problems, on balance, it's a very good picture and one worth your time. Currently, it's available streaming from Netflix, though the copy isn't great due to film degradation. I'd love to see the film after some sort of color restoration.
The film begins with a guy (Patric Knowles) approaching the Dacey family in Jamaica to buy their plantation. However, it's been in the family for generations and they aren't interested in selling. A bit later, he returns and here is where the plot gets weird. He brings along two distant relatives of the Dacey's and a diver (Ray Milland). Why? Because more than a hundred years earlier, relatives were in the process of buying the plantation and no one was sure if the deal was completed or not. This is because the two branches of the family (those buying and those selling) had met on a ship that subsequently sank--and no one survived to tell whether money had changed hands or the contract signed. Now, Knowles' character proposes to have his diver explore a ship wreck to see if proof can be obtained. Not surprisingly, with so much at stake, it's not surprisingly when a murder occurs. But who is responsible? And, what happens when a treasure chest IS found? The film has some decent acting but in particular, I liked the script. This is because although the plot WAS complicated and strange, it had lots of twists and surprises. I particularly liked the ending--now THAT was a big shock. Apart from one or two minor quibbles (such as the romance involving Wendell Corey's character--it just happened too fast to be realistic as well as WHY would a servant be called 'Human'--what sort of name is that?!), the film is a dandy adventure that is well worth seeing.