A film about a group of young baseball-enthusiasts who test the terrifying myth of Mr. Mertle owning a freakishly large and dangerous dog in his backyard.A film about a group of young baseball-enthusiasts who test the terrifying myth of Mr. Mertle owning a freakishly large and dangerous dog in his backyard.A film about a group of young baseball-enthusiasts who test the terrifying myth of Mr. Mertle owning a freakishly large and dangerous dog in his backyard.