गूफ़

At the beginning of one scene, the clock can be shown displaying "13:32", and during the very next scene the clock can be seen displaying "13:31".

Around 23:50 into the movie (when they are in the clothing store) you can see a person walking outside the store as the camera is changing angle.

The eyes are still blinking from a side shot after the person is dead.

59:37 Legs of several people moving can be seen in a reflection on a window.

Judging from her map of crossed-off regions, Jenai oddly chose some of the least-populated parts of Iceland to start checking for people, like the northwest corner, before the southern shoreline that has far more towns and villages. She also got through huge stretches of land very quickly, given that it is still summer (Riley wears a T-shirt outside) when she has much of the western and northern parts of the island crossed off. Simply moving through all the homes in Reykjavik would take weeks if not months. Plus, while she's talking to Riley Jenai crosses off some houses with red tape without having actually knocked on the doors.

Throughout the movie, there are numerous errors in geography. Most notably: It takes a lot longer to get from Reykjavik, where the couple lives, to Vik, where Riley goes looking for Jenai during the movie's finale, than it takes for a bit of water to heat up. The drive to Vik is actually a few hours.

Nils is almost dying from thirst despite living in a lakeside cabin.

Riley flips through the television channels to see what is working, and discovers that only the news stations aren't broadcasting. Yet, new to the area, he would have no idea what the news channels were. He might make the assumption this was what was going on since he came across all sorts of broadcasts but no news, but this is an iffy assumption given that even news channels don't necessarily have active news programs all the time.