Ab Tumhare Hawale Watan Sathiyo is about 1971 during the Indo-Pak war and the formation of Bangladesh, Lt. Commander Vikramjeet Singh has a ship in his command and a regiment of soldiers of the Indian Army, commandeered by his dad, Major General Amarjeet Singh.
The ship comes under attack by a submarine of the Pakistani Navy, undergoes damage, and sinks along with Vikramjeet, but not before he courageously rescues about a hundred of trapped army soldiers.
Years later, Vikramjeet's son Kunaljeet joins the army as a Captain, but he lacks the values his dad and grandfather had in them about serving the country selflessly. He just wants to be employed with the army for a couple of years, then re-locate to the U.S., run a business, and make lots of money.
In order to accomplish this he always makes up excuses of not going to the front. He falls in love with Shweta Bhansali, and decides to stay in the army in order to be close to her. In order to achieve a medal, he fakes heroism; then carelessly jeopardizes a planned attack on terrorists and as a result several terrorist escape to their hideouts.
Disciplined and chastised, an injured and humbled Kunaljeet awaits to meet his sweetheart - only to find out that she is in love and married to his senior Officer Major Rajeev Singh. The only thread binding him to the army is broken, and it is then Kunaljeet finds out that the terrorists in collusion with rebel Pakistani officers are planning to bomb the Bhagwan Shivji's Amarnath Temple in Jammu & Sikkim in order to wipe out the Hindu religion and culture once and for all. Will Kunaljeet act accordingly to save some lives, or will his rashness result in more casualties?