Nathan Drake has always had a thirst for adventure: the bigger the risk, the bigger the adrenaline rush. Throughout the years, we've seen him exude confidence, recklessly throw himself into danger, and do it all with a carefree attitude and a joke to complement it. But Nathan Drake has slowly been unraveling before us, making us more skeptical of him. It's clear that he's been putting up a front concerning some issues from his past, and Naughty Dog is ready to provide some closure in Uncharted 4: A Thief's End.

Uncharted 4 will still have the humor the series is known for, but Naughty Dog also wants to take the story to a different level. The overall narrative has slowly been building to this point. Uncharted 3: Drake's Deception had the most startling revelations, diving into Drake's past. We found out Drake grew up in an orphanage. His father gave up custody of him to the state after Nathan's mother died by suicide when he was five years old. We also discovered that "Drake" isn't really Nathan's last name. Then we saw him struggle with his lust for adventure and his feelings for Elena. In Uncharted 3, it almost ended their marriage, but Drake finally came around, putting back on his wedding ring, choosing her.

"Nathan Drake is an interesting character in that he's got this facade," says director Bruce Straley. "Everybody believes that he's quippy and he's off the cuff, but over the course of each game, you've seen that he's actually driven by something way deeper than what's on the surface."

For Drake, the desire for family and tackling his abandonment issues have been a part of each game. As we've seen, Nathan has been building his own family since he ran away from the orphanage at the tender age of 14. He found a father figure in Sully and a romantic partner in Elena. "The theme throughout all these games is family," says Nathan Drake's voice actor Nolan North. "And he's made his family because he thought he lost so much."

Uncharted 4 takes place three years after the events of Uncharted 3. Drake has settled down with Elena, leaving his treasure-hunting days behind him. But his comfortable lifestyle is cut short when his long-lost brother, Sam, appears. All this time Drake thought his brother was dead, and Sam's reemergence brings up plenty of emotions. "He's gotten settled into his life with Elena, and I think when you throw something into the mix after so many years and it's back, it's heart-wrenching," North says. "It's something that you thought you lost. Now for somebody to show up, it's almost like you're seeing a ghost."

Drake has never acknowledged his brother, so we never even knew he existed. However, Sam is key to a lot of what Drake has been hiding. "As we learned in Uncharted 3, Drake has a lot of secrets," says writer Josh Scherr. "Some [are secrets] that he's never told anybody else, and a lot of those secrets are buried in his past. And who better to help dig up those secrets than a long-lost family member?"

"I think that's where a lot of people's inner pain comes from...things that have happened early in your life and whether those experiences are scarring or they were so great that they just kind of linger with you," adds creative director Neil Druckmann.

Drake and Sam have a complicated relationship. They didn't necessarily part on bad terms, but Drake thought he lost Sam, which devastated him. Now he has his brother back, but he can't just focus on rebuilding that relationship. Sam also needs Drake's help, asking Drake to join him on a high-stakes adventure to find a mythical pirate colony.

Sam is also a thief and has definitely lived a more troubled life than Drake, but he still has the same desire for adventure as his brother, though he's even more reckless. Also, don't expect everybody to be happy with Drake's decision to help his brother and return to his treasure-hunting lifestyle. "Drake is doing something for his brother, but there is a cost to that, which maybe everyone else is not going to be keen on that idea," Scherr teases.

It's not hard to read between the lines that Sully and Elena don't fully support this decision. Conflict between Drake's newfound family and his biological family is just one dilemma he'll confront in Uncharted 4. However, Drake isn't just getting back in the game for a joy ride; the stakes are high. Naughty Dog didn't reveal exactly what's at stake, but in a cutscene we saw during our visit, Sam did say, "We're buying my life back." As we know, Nathan is a good guy at heart and there's no way he'd leave a family member in peril, even if it causes conflict.

"Family itself is complicated," Scherr says. "You have some relatives you get along with, others that you don't, and others that it depends on the day. Drake's brother definitely had a formative influence over his life. And regardless of what [Drake] thinks of his brother, there are things that you'll do for family that you wouldn't necessarily do for anyone else. There's that feeling of nagging obligation."

Another dilemma Uncharted 4 brings up is Nathan's obsession with putting himself in harm's way and loving the thrill of the hunt. Naughty Dog wants to explore why Nathan would find this life enticing and what drives him to it.

"Each of the characters that we've introduced to [Nathan Drake's] world and his universe are pulling different aspects of him out, but we've also left a few things, kind of some loose ends here and there, and we still have a story to tell about something else inside of him," Straley says. "What's driving this guy? What makes him adventure? What makes him make these choices that he's driven to make? Who is Nathan Drake and what makes him tick? And that's really interesting to me."

"One of the themes that we're exploring with Uncharted 4 is the idea of obsession," Druckmann adds.  "Passion can become obsession. Obsession can become an addiction, and they're all kind of very similar ideas. But they have a cost and this idea [we wanted to explore is] that every treasure that Drake pursues has a cost to it - an emotional cost, a relationship cost sometimes. It sounds dark, but again that to me is the humanity within who Nathan Drake is. There is a two sides to everything that we do in life, and in this game we're going to try to explore those two aspects of it."

In the end, Nathan Drake can't have it both ways. As Druckmann says, "You can't have the adventure life and settle down with the person you love." This isn't the first time Drake has had to face this dilemma, but this could be his last chance to make the right choice and his brother will no doubt complicate what he chooses.

In our time with Naughty Dog, it was clear that Uncharted 4 focuses on who Nathan Drake really is, confronting the skeletons in his closet and coming out with a great payoff for being invested in the series for all these years. "We're trying to explore who Nathan Drake is as a person," Druckmann says. "People make mistakes, people are imperfect, they're vulnerable at times, [and] they hurt other people even when they don't mean to.... We're delving a little deeper than we have before into the human side of Drake."

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