Challenge to Lassie is an American drama directed by Richard Thorpe in Technicolor and released October 31, 1949 by MGM Studios. It was the fifth feature film starring the original Lassie, a collie named Pal, and the fourth and final Lassie film starring Donald Crisp. The movie is based on Eleanor Stackhouse Atkinson's 1912 novel Greyfriars Bobby which in turn is based on the true story of Greyfriars Bobby. Twelve years after starring in Challenge to Lassie, Crisp would star in another movie based on the novel, Greyfriars Bobby: The True Story of a Dog.