.........The plot follows Dastan (Jake Gyllenhaal), a street urchin in Persia, historically in the Persian Empire in the sixth century. After showing courage in the market place, he is adopted by the king. Fifteen years later, Dastan, and his royal blooded foster brothers Garsiv and Tus lead the Persian army in an attack on the sacred city of Alamut, under the assumption that the city's people are selling weapons to their enemies, as shown by Nizam (Ben Kingsley), the King's brother and adviser. As Garsiv leads the initial assault, Dastan decides to lead a surprise attack with his friend Bis (Reece Ritchie) against the orders of his brother. He manages to open the eastern gate of Alamut and prevents further casualties. During the fight in the city, Dastan defeats one of Princess Tamina's (Gemma Arterton) guards who was in the possession of the mythical Dagger of Time. The dagger gives its owner the ability to go back in time for a short period so that the user can try to correct any mistake or redo any moment. Alamut falls to the Persians, Tamina is captured and is offered as a wife for Tus, which would make the city of Alamut a part of the Persian Empire.

The Persians celebrate their victory, but during the celebration Prince Dastan is fooled into presenting a poisoned gown seemingly given to him by Tus to King Sharaman (Ronald Pickup), which fatally burns the king. Prince Dastan is held as the perpetrator of his father's murder. He escapes the castle with Princess Tamina while Bis, his best friend, is killed trying to save them. Together, they embark on a journey the Prince wants to prove his innocence, while Tamina wants to safeguard the Dagger of Time. On the first night, Tamina attempts to kill the prince and recover the dagger, but Dastan accidentally activates the dagger and learns about its ability to rewind time for one minute and in doing so, prevents Tamina from attacking. Dastan believes that Tus knew about the dagger and framed Dastan for their father's murder in an attempt to seize the throne and the dagger, thus becoming the most powerful ruler of Persia...........