Aiyaary is an espionage thriller about two Indian army officers, Colonel Abhay Singh (Manoj Bajpai) and his subordinate Major Jai Bakshi (Siddharth Malhotra). The two officers are a part of a military intelligence unit called DSD – Data & System Diagnostics. The motive of this unit is to put important numbers on surveillance and tap phones to gain important information.
The two officers have a fallout after Jai happens to lay his hands on an earth-shattering information regarding the Indian army while tapping a phone. This leads Jai to go against the whole system. He does a disappearing act and eventually Abhay is assigned to trace Jai. He is given 36 hours to get to Jai, who is the only one who knows of the dirty secret that can bring down the whole government.