Battle Circus is a 1953 American war film directed by Richard Brooks, who also co-wrote the screenplay with married writing duo Laura Kerr and Allen Rivkin.

A young Army nurse, Lieutenant Ruth McCara, is newly assigned to the 8666th MASH, a mobile field hospital constantly on the move during the Korean War.

She initially experiences an uncomfortable welcoming by the unit's hard-drinking, no-nonsense chief surgeon, Major Jed Webbe.

When a young Korean child needs special care, Ruth entreats Jed to perform an open-heart operation, despite the reservations of the unit commander, Lieutenant Colonel Hilary Whalters.

Jed is a relentless taskmaster, demanding Captain John Rustford fly desperately needed blood supplies at night, even in the teeth of a fierce storm.

Traveling cross-country, he sets out on a perilous journey, attempting to meet up with the nurses who have gone on ahead by rail to a preset rendezvous.

As appearing in Battle Circus, (main roles and screen credits identified):[5] According to Richard Brooks (in an interview filmed for the 1988 Bacall on Bogart documentary), Battle Circus was originally called MASH 66, a title rejected by MGM because the studio thought people would not understand the connection to a military hospital.

The title of the film actually refers to the speed and ease with which a MASH unit, with its assemblage of tents, and portable equipment, can, like a circus, pick up stakes and move to where the action is.

[7] Allyson was initially afraid of acting with Bogart, but her recent roles in light romantic comedy had typecast her and she was encouraged by the studio to attempt more serious fare.

[8] The camp commandant offered the film crews use of the base facilities, including his house for the lead actors, after initial scenes were finished.

While commending Battle Circus for being a revealing and engrossing wartime drama, reviewers noted that the tepid love story distracted.

studiously traces a routine wartime romance against an absorbing, often tingling background of a mobile Army surgical hospital at the Korean front.

Unfortunately for the general pace and impact, considerable time is allotted to a dawdling and familiar personal drama, the romance of an Army surgeon and a rookie nurse.

For, in depicting the hairbreadth, makeshift operations of one of these heroic units, channeling its precious cargo to safety under constant exposure to the enemy.

"[13] A retrospective review in TV Guide noted, "This movie was the forerunner to M*A*S*H, chronicling a Mobile Army Surgical Hospital in the Korean War.