Produced by McLaglen and screenwriter James Lee Barrett, the film stars Dean Martin, Honor Blackman and Brian Keith.

In the frontier of New Mexico Territory, Joe Baker is an aging bandit determined to do "something big" before his fiancée Dover McBride arrives from the Eastern United States.

Baker must deal with outlaw Jonny Cobb and his ruthless sidekick Angel Moon, while also opposing his plan is the cantankerous Colonel Morgan, who is about to retire from the U.S. Army command in the territory while his wife Mary Anna is arriving from the East to accompany him home.

Cobb and sidekick Moon meet the trader Malachi Morton in the desert to buy the gun, which has been stolen from a federal arsenal.

Baker finds the bandit's treasure in the town church, but as his men celebrate their riches, he is haunted by Dover’s parting words.

Vincent Canby of The New York Times found it perversely humorous: "Like being stuck on a subway, or bearing witness to a mugging on the other side of the street, watching Something Big is a group experience of a contemporary, if secondary, order.

He is the centerpiece of a fiction that occasionally recalls the sentimentality of John Ford, with mock seriousness, as well as the inane cheeriness of those TV Westerns whose heroes never die, but just go into reruns.