The Killer Shrews

Thorne Sherman and his first mate Griswold deliver supplies to a group on a remote island. The group, consisting of a scientist named Marlowe Cragis, his research assistant Radford Baines, the scientist's daughter Ann, her fiancee Jerry Farrel, and a servant named Mario, meet the captain and his first mate and advise them to stay with them in a house because a hurricane is approaching. Thorne goes but Griswold stays with the boat.

On the island, a doctor works to make humans half-size. This, apparently, will reduce world hunger as smaller humans would presumably eat less. Unfortunately, his experiments have also created some giant, venomous shrews. Thorne and Ann begin to fall in love, which angers Jerry. As the shrews run out of smaller animals to eat, they eat Griswold and close in on the people in the house, ultimately breaking in through the basement. It is discovered that the shrews have a poisonous bite, as a small single bite is enough to kill Mario. The poison kills Radford, and the shrews force the group (save for Jerry, who wants to stay) out of the house to escape to Thorne's boat. They do this by making impromptu armor out of oil drums and crawl to the beach lashed inside them. Jerry is killed by the shrews after he changes his mind and chases after the others, but the rest of the crew (Thorne, Ann, and Marlowe) manage a successful escape to the boat.

The killer shrews
The "shrews" in this ultra-low-budget film are small dogs dressed in animal skins designed to make them look vaguely like large shrews (they even bark audibly in many scenes). Puppets made from similar animal skins were used for closeups. In reality, shrews are smaller than a mouse, being the smallest known mammal. As stated in the film, though, they do have a venomous bite (harmless to humans) and they have to kill and eat prey constantly in order to maintain their amazing metabolism.

in my opinion this is pretty cheap