Love doesn’t work when two people are apart. It only works when they’re together – at least that’s what best-selling author Nicholas Sparks leads fans to believe.

The movie, “Dear John,” based on Sparks’s best-selling book of the same name, chronicles the lives of John Tyree (Channing Tatum), a soldier home on leave, and Savannah Curtis (Amanda Seyfried), a college student in North Carolina.

The two meet when John rescues Savannah’s purse after it falls off a pier into the ocean. It’s then when John realizes his life changes.

They quickly fall in love, like most of Sparks’ protagonists, but before their love can fully blossom, John must report back for duty – something that could pose a threat to their budding relationship.

“[Leaving] was one of the things that they said (was difficult),” Tatum said about meeting individuals in Special Forces. “It’s just the patience and the knowing that you’re going to go back. You’re surrounded by danger, but you try not to think about that. You just keep thinking I get to go back in two months and three months and four months or however long it is. And just getting anything in the mail just makes your day. I can’t imagine being away from the person I love for that long.”

As Savannah waits for John, she tries to return to her normal life as a college student, but she’s unable to keep her composure.

“It’s hard to connect, when you have that much time away from somebody, it’s hard to stay connected in each other’s lives,” Seyfried said. “So that’s one thing that you’re really fighting. If you lose that battle, I still think that if it’s meant to be, it’s going to come back to you. Love is just like that all the time. “

Then, terror strikes New York City on September 11, 2001, and John and Savannah are faced with a familiar situation: John must choose between love and war.

Over the next seven years, they write to each other, trying to keep their relationship strong. With time, weekly letters turn into monthly ones – time and separation divide them.

Tatum said he’s never written a love letter but offered these words of wisdom:

“I think if you haven’t written, guys, especially, guys, listen, if you haven’t written a love letter in a long time, you don’t have to sit and mail it. You don’t have to do anything, just write whoever your loved one is, write her something and you’ll be amazed at the reaction.”

While Sparks is known for his heart-wrenching love stories like “The Notebook,” the plot of this film may hit home for college students whose girlfriend or boyfriend is deployed overseas.

“College-aged kids are finding each other, and it’s that whole challenge of actually realizing that this is really the person that you’re going to spend the rest of your life with,” Seyfried said. “In our story, they met that young and it happens and it’s realistic and so that love can thrive if you let it.”

While many moviegoers might expect a specific type of ending, they could be surprised with where these characters end up.

“I’m very, very satisfied with the end of the film,” Tatum said. “We as a unit on the movie, we talked about it a lot. It’s just really real, I think, the movie. It’s a little different than a lot of his other books. I think it has a little more bite to it and maybe just because the content matter is very relevant right now, it’s very, very prevalent.”

“Dear John” premieres in theaters Friday.