Four life-long buddies go on one more "Guys Only" hunting trip together, but they don't come back when they were supposed to. Now the local law enforcement who were also friends with the four have to find out what happen to them. While the officer is investigating, two of the four men find themselves in a cave dealing with something that they have never encountered before. The two have to figure how to communicate with the creatures, how they got there, and how to get themselves out alive....