Don (1978)

A ruthless gangster named Don is killed during a scuffle with the police. Since only DSP Desilva knows of this incident, he recruits another person named Vijay who is a spitting image of Don. Vijay is planted in Don's place in Don's gang and DeSilva has a plan to nab the entire gang in this way. But when Desilva dies during a raid, the secret that Vijay is not Don is also buried with him. Now Vijay is on the run - from the police and the criminal gang - and has to find the last piece of evidence to prove his real identity before it is too late.