1x28 - The New Adventures of Lucky Luke

Lucky arrives in Green Valey, Alabama, a town obsessed with cattle and domineered by the largest cow herd rancher. When the only sheep-herd mourns individually named sheep, believing them to be devoured by a huge monster, Lucky soon smells a rat, but still has to prove his suspicions, helped or rather hindered by a clumsy self-invited 'monster hunter'.