A newly married couple is on their honeymoon in Hawaii, when they hear about some killings in Honolulu, and begin to suspect that the killers might be on the very same island as they are. I used to live in Hawaii, so I appreciated a lot of the scenery here, even though a lot of it was actually filmed in Puerto Rico(to save money). It does a pretty good job of building suspense, is ripe with red herrings, and the acting is fine. Nothing else really stands out much, but it makes for a decent mystery/thriller. There were a couple of cheap "jump scares", and a few other minor quibbles, but not much else worth mentioning except for what's below.
This movie doesn't really stand up well to repeat viewings. On your first viewing, the filmmakers do a pretty good job of leading any suspicion you have away from the two leads, but on your second time around you realize they were essentially doing so by lying to you, otherwise the twist wouldn't have been possible(and I suspected as much the first time around). I've seen other people explain this away by saying "Oh, well they were just staying in character." Pfft, during the flashback scene towards the end, while on the trail, they're clearly shown to be discussing their situation as who they really are(the killers). And their behavior(body language, voice inflection, etc.) when alone clearly indicated that they thought the other two were the killers. So that excuse only goes so far. Basically, I thought it was a bit cheap. Oh well.