Lalkar (The Challenge) (1972)

India is in a state of war with Japan and former Colonel Kapoor's sons, Rajan and Ram are both with the Indian Armed Forces. While Rajan is a Wing Commander with the Indian Air Force, Ram is a Major with the Indian Army. Rajan is in love with a doctor named Usha Choudhury, and both plan to get married. Then Usha meets with Ram, who unknowingly falls head over heels in love with her. Before anything can be finalized, Rajan is asked to bomb a secret Japanes airport located in a mountainous valley. While carrying out his duties, he finds out that his mission has been compromised, unable to return, his plane is shot down and he is believed to be dead. The Indian Army wants to destroy this secret airport and sends a crack Commando unit under Major Ram, who sets out to carry out this task. What Ram does not know is that this mission has also been compromised and he and his men are all set to walk into a carefully planned trap by the Japanese - who will ensure that no one survives to tell.