Goofs

Mac's facial hair is constantly changing between shots throughout the film.

During scenes on the beach, snow appears and disappears on the mountains of Rhum in the background between shots.

When Happer leaves his penthouse office to enter his adjacent apartment, he uses a remote control to reveal the apartment's single doorway entrance. Yet in the next sequence, Happer is shown cooking in the kitchen, with the same entrance in the background double-doored.

The aforementioned "grey seals" segment is clearly stock footage, unmatched to the original material surrounding it in the rest of the film.

Just before the first RAF Jaguar flies over the car, raindrops can be seen in the inside of the open door as they are feeding the rabbit. They stand up to look at the jet, and the car's roof has no raindrops on it.

Marina and Danny are looking at what Marina says are grey seals but which are Californian fur seals, which aren't native to Scotland.

Mac and Danny walk into the lab and Geddes tells him to "Close the door. This is a controlled environment." In a following long shot, you can clearly see a large loading dock door open to outdoors on the right side of the frame.

However in the UK 'controlled environment' refers to access, not isolation from outside contamination.

While Mac is on the plane to Aberdeen, arrival time is announced as 1:45 local time. Shortly after arrival, he goes to the laboratory and the clock shows 12.30. Marina going to lunch reinforces the clock time.

When they hit the rabbit, Oldsen says "Why don't we kill it? Hit it with something hard", to which Mac replies "You've already done that with a 2-ton automobile!" They are in a Mark 5 Ford Cortina (and a lower spec model with a 1.6 liter engine) which only weighs a little over 1 ton. However, Mac is American and an American car of that style might well weigh 2 tons. Moreover, it's unlikely that he'd know the weight of a British car and it was also just a figure of speech (hyperbole).

Mac's watch left on a rock would not just lie there as waves hit it unless it were attached to the rock.

There is no way the pilot would leave the helicopter where it is on the beach overnight, especially since it is obviously below the high tide line.

While the road on which Danny and Mac stop the car is obviously little traveled, it is actually illegal to park on an unlit road in the UK with all lights off; sidelights at least must be left on. Danny should know this. Danny likely does know this but chooses to ignore it. In rural areas like this locals take a flexible attitude to minor road laws.

Victor, who "has been coming here for years" and is very familiar with all of the townsfolk, is introduced to Ben (the morning after the ceilidh) as though a stranger (and even though Ben was present during Victor's song).