Review of Graveyard Shift

I first saw this in the early 90s on a vhs. Revisited it recently. Workers working in a mill from evening till morning to avoid the extreme heat encounter rats infestation due to the mill being next to a cemetery. The mill foreman hires a rat exterminator but he is unable to kill all of the rats. He explains to one of the worker that during the Vietnam war, the soldiers used to cut open a portion above the abdomen of captured soldiers n make a hungry rat nibble on the wound. To make the rat pierce inside the wound, the soldiers used to take a metal bucket n cover the rat n heat up the bucket with flames. This short story is much better than the entire film. This film has lack of tension n the kills r nothing memorable or gory.