The Graveyard Rats (Unabridged‪)‬

A grave robber glances at a coffin he's recently unearthed and opened, and, enraged, he witnesses his prized corpse being drawn out the chewed end of the coffin into a subterranean burrow by the graveyard rats. Without thinking, he dives in after it and, crawling through the underground maze, pursues the corpse only to discover he is being pursued by the gargantuan rats and something far more ominous...the undead.