Lucky Luke: The Ballad of the Daltons (Lucky Luke: La ballade des Dalton) is a 1978 animated film based on the comics by René Goscinny and Morris. The story, like the previous film Daisy Town, is an original story, but it was adapted into a comic in 1986.
Synopsis
The Daltons have inherited a fortune from their Uncle Henry, but can only inherit it under the provision that they kill the judge and jury who had him hanged. Lucky Luke accompanies them and ensures they don't actually kill anyone.