Bonanza S1 x E21

In this episode, a young bargirl named Rosita Morales pretends to be Isabella Marie Inez de la Cuesta, a Spanish noblewoman, to claim a land grant that includes a significant portion of the Ponderosa. The Cartwrights are forced to act when the De La Cuesta family tries to seize the land, threatening both the Ponderosa and local Carson Valley settlers.