Heflin started with acting in a student theater group at the University of Oklahoma. This path eventually led him in the early 1930s to Broadway. In 1936, he turned in his first Hollywood film.
Heflin was not a hero type, and therefore was not a glamorous Hollywood movie star. He convinced rather in edgy character roles and was awarded an Oscar in 1943 for his role in the film Johnny Eager. Heflin starred in numerous westerns, among other things, in George Stevens ' cult Western Shane ( 1953). In 1948, he starred in The Three Musketeers alongside Gene Kelly.
1971 Heflin suffered while swimming in his swimming pool a heart attack. He died after a seventeen -day coma.
The actress Marta Heflin was the niece of Van Heflin.