Mason Alan Dinehart

Mason Alan Dinehart is an American business consultant and retired actor best known for his role as a youthful Bat Masterson in 34 episodes between 1955 and 1959 of the ABC/Desilu television series The Life and Legend of Wyatt Earp, starring Hugh O'Brian in the title role of the frontier marshal Wyatt Earp. He is also known as Mason Alan Dinehart III, Alan Dinehart III, and Mase Dinehart.

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THE LIFE AND LEGEND OF WYATT EARP · S2, E39

The Time for All Good Men

The owner of the Big T Rance Purcell and his foreman Gus Andrews trap Earp alone at Stony Wells. Earp outnumbered 30 to 1 is running out of water and ammo. Purcell wants Earp to suffer as several famous outlaws come together to help Earp.
THE LIFE AND LEGEND OF WYATT EARP · S2, E14

Nineteen Notches on His Gun

The Dutch Henry gang is rustling cattle and killed ranch hands on some of the smaller ranches around Dodge City. Sheriff Bassett is sick and Deputy Tillman is gone so Earp and Bat decide to go undercover into the gang rather take a posse.
THE LIFE AND LEGEND OF WYATT EARP · S2, E13

Take Back Your Town

The George Morris gang tries to take over Dodge City while Earp and Sheriff Bassett are gone. They succeed but Bat escapes capture to catch Earp. The two decide to return to Dodge City alone but the odds against them are not promising.
THE LIFE AND LEGEND OF WYATT EARP · S2, E16

Justice

Two Cheyennes have been killed, which can start a new Indian war. The Cheyenne chief plans to attack Dodge City for revenge. Wyatt Earp has no other choice but bring the killers who were scratched by the Cheyenne woman to justice.
THE LIFE AND LEGEND OF WYATT EARP · S3, E33

Two

Earp and Bat leave Dodge City to go after the remaining three members of the Dry Gulcher Gang who killed Mr. Brother. They find them but a shave tail Army Lieutenant interferes with their capture of one them impersonating an Army corporal.