Walker had a role in Kraft Suspense Theatre (episode "Portrait of an Unknown Man", alongside Robert Duvall).
He had a supporting role in the Rock Hudson–Doris Day comedy, Send Me No Flowers (1964).

Frank Sinatra cast him in the leading role in the war drama None but the Brave (1965), the only film Sinatra directed.
After doing some guest appearances in The Lucy Show he fought a grizzly bear in Paramount's Western, The Night of the Grizzly (1966).
He starred in a family adventure movie shot in India, Maya (1966).

Walker had his biggest hit to date when he played the meek convict Samson Posey in the war drama The Dirty Dozen (1967).

Walker returned to Westerns with More Dead Than Alive (1969).
The New York Times described the actor as "a big, fine-looking chap and about as live-looking as any man could be.
And there is something winning about his taciturn earnestness as an actor, although real emotion seldom breaks through".

Walker had support roles in two comic Westerns, Sam Whiskey (1969) and The Great Bank Robbery (1969).
Walker had a role in Kraft Suspense Theatre (episode "Portrait of an Unknown Man", alongside Robert Duvall). He had a supporting role in the Rock Hudson–Doris Day comedy, Send Me No Flowers (1964).
Frank Sinatra cast him in the leading role in the war drama None but the Brave (1965), the only film Sinatra directed. After doing some guest appearances in The Lucy Show he fought a grizzly bear in Paramount's Western, The Night of the Grizzly (1966). He starred in a family adventure movie shot in India, Maya (1966).
Walker had his biggest hit to date when he played the meek convict Samson Posey in the war drama The Dirty Dozen (1967).
Walker returned to Westerns with More Dead Than Alive (1969). The New York Times described the actor as "a big, fine-looking chap and about as live-looking as any man could be. And there is something winning about his taciturn earnestness as an actor, although real emotion seldom breaks through".
Walker had support roles in two comic Westerns, Sam Whiskey (1969) and The Great Bank Robbery (1969).
Clint Walker