Goofs

For about 4 brief seconds, one shot of the "crocodiles" head swimming on the surface in the dark reveals it is actually an alligator which can be determined by the bump of it's nose, raised eyes, shape of it's jaws and curved snout. Crocodiles and alligators are different species. There are No Alligators in Australia.

As they drive along the river bank at the start of the movie, the water level of the river can be seen, but after the cave is flooded from heavy rain and they exit into the river, the water level is the exactly same.

Heavy rain floods the cave, but as they emerge up the riverbank, the ground is dusty and dry.

Throughout the movie, the crocodile kept changing back and forth between color and size.

As the group first begin exploring the cave, there is an obvious back pack left at the point of descent when they walk away. Same yellow and black back pack reappears on the actors back later, then disappears then reappears.

In one scene, the crocodile can be seen almost fully emerged from the water performing a 'death roll', but there is no independent movement of it's tail, legs or torso that could make the death roll physically happen.

As they explore the cave, the lamps on their helmets are at an angle upwards, and not directly ahead of them where they would be useful.

After the crocodile is shot there is an underwater view showing the dead animal sinking in the blood stained water but it is lit from below. It would appear that the image has been flipped vertically and the croc was actually floating to the surface and the light from above.

At the latter part of the movie, the crocodile is seen moving forward in a straight line swimming on the surface of the water, but their is no tail movement to propel it through the water. (Salt Water Crocodiles do not swim with their feet)

Jennifer pulls a digital camera out of a backpack which has been submerged underwater and turns on the camera. The camera works without any issue. Had the camera been submerged as long as it was, the camera would fail to operate properly or even at all.