Bonanza: S2 E10 - The Last Viking Bonanza

Gunnar is a long-lost relative of the Cartwright family. When Gunnar arrives at the Ponderosa, the family takes him in for the evening. Gunnar is the brother to one of Ben Cartwright's late wives. Unbeknownst to the Cartwright family, Gunnar is also the leader of a band of criminals called The Comancheros. Little Joe is visiting his girlfriend away from the ranch. When Little Joe and his girlfriend are kidnapped by The Comancheros, the Cartwrights and Gunnar are forced into a difficult situation.