The Brothers Drake is the sixteenth chapter in Uncharted 4: A Thief's End, and follows up the events of the first chapter, The Lure of Adventure.
Plot[]
While Elena tends to Nate's wounds, he tells her about Sam.
In a flashback, young Sam and Nathan Morgan arrive outside a mansion where their mother Cassandra Morgan's belongings are held. Nobody appears to be there. They climb the rooftops and enter the house through a window in the attic. Inside, they discover rooms with various kinds of historical artefacts and journals. When they find a polaroid camera, they take a picture of themselves wearing historical helmets.
In one room, they find their mother's journals. Whil they study them, the light is switched on and an old woman points a pistol at them. She has already called the police. Sam explains they were only looking for her mother's diaries. The woman, Evelyn, realizes that they are Cassandra Morgan's boys. She tells them that their mother was a great historian who worked for her and lets them have the diaries. When the police arrives, she wants to send them away. On the way to the door, however, she collapses and remains lying without signs of life.
Nate wants to help her, but Sam insists that there is nothing they can do for her and that they have to leave. Fleeing from the police, the boys arrive at Sam's motorcycle and drive away. After some time, they make a stop. Knowing that they cannot return to their former lives, they decide to drive away and try to complete their mother's work. Since her mother was convinced that Francis Drake had heirs, they take the new identity of Sam and Nathan Drake.
After finishing, Nate says to Elena that now she knows everything. She answers that she doubts whether that's everything, but it's a lot.