Git!

Git! is a 1965 American drama film directed by Ellis Kadison and written by Homer McCoy. The film stars Jack Chaplain, Heather North, Leslie Bradley, Richard Webb, Hanna Landy and Emory Parnell. The film was released in October 1965, by Embassy Pictures.
Plot.
Deke, a 17 year-old itinerant orphan from a boy's home, is arrested by the authorities after he stops Art Finney, a trainer for a wealthy California dog breeder, Andrew Garrett, from shooting "Rock", a renegade English setter and alleged animal killer. Garrett has Deke remanded to his custody and gives him a job assisting an uncooperative Finney and also working with Rock, whom Deke asserts can become a fine hunting dog. Finney and Garrett don't agree, but gradually come round to accept his belief in Rock.