[TOMT][MOVIE] Cave type movie where they sit in chair and stare at a hole in the wall and try to dig it out and they go crazy.

I am trying to remember the name of this movie I seen on amazon prime video maybe around 6-8 years ago because I want to find it and rewatch it. Rough details I can remember was that is was a cave like movie where 2 guys were attempting to dig out a hole that was in the wall of a cave. Most of the movie was about them digging but it seemed like the hole never really got much bigger. There were scenes where they would just sit in a chair and stair at the hole in the wall with a spotlight on the hole and eventually it drove them mad. I think the one guy wound up killing other dude and then himself at the end. I remember the title was a little long and also unusual as far as movie names go. I want to say that maybe there was a Tom or Tim but I could be completely wrong about that.