The day fans of Fox’s Fringe have long dreaded has arrived as tonight the sci-fi drama says farewell in a special two-hour finale that brings to a close the five-season journey.

"I'm sad to see it end, but I hope we're going to go out with a bang," star Joshua Jackson said in a conference call with reports..

While the first hour of tonight's finale is solely focused on Anna Torv's character Olivia Dunham, Jackson teased the second episode will tie everything together.

"In the finale, as much as Walter may be called on to make a sacrifice and the gang in general is trying to implement Walter and Donald's plan, it was, at least in the script, it read pretty spread across all the players," he said. "Everybody had their piece of the story. Ultimately, Peter's role, as it's always been, is to be the dutiful son and husband and father. That plays itself out in a very specific way."

Whether that way involves some kind of sacrifice on the part of his character, Jackson wouldn't reveal. However, he did note that Peter had proved he was more than willing to make that sacrifice in the name of family.

"Peter has already given his life for Walter. The end of the storyline of 'Peter and the Machine' was choosing for his family to live and him to cease existing," Jackson said. "Yes, I think it would not at all be outside Peter's thought process to sacrifice himself for a family member. It's just a question of which family member he would sacrifice himself for. The journey of Walter's crisis of conscience, as much as he's worried he's going to become -- the price of genius has been hubris. That hubris has been incredibly destructive. Walter is essentially afraid of becoming fully Walter because he's not sure that he cannot become that egomaniac again. The gift that Michael gives him, this empath, is to free him from that fear, to release him from the small-mindedness of thinking there has to be some sort of price to pay for being the best version of himself as he can be. That's what gives Walter his new lease on life. It's also what gives Nina Sharpe the ability to accept her fate towards the end of her episode."

The series was given a final season to wrap up its story, something Jackson acknowledges wouldn't have occurred without the love of the passionate fan base.

"As much as every TV show is trying to reach out to its audience, it really is the audience itself in our case who continued to drive their own interests and continued to keep each other engaged as much as we try to help them along," he said. "The community of Fringe became totally self-supporting. To talk about Fringe not just as a narrative experience on screen, I think one of the more interesting things to come out of it is that community building on the show and how powerful that can be in tipping the scales to a show surviving or failing. By traditional metrics, our show would have been off the air at least last year, but probably two years ago, except the passion of our fan base made it impossible for our show to be dismissed. Maybe the way that even ten years ago science fiction shows ten years ago were lost. The fan base and the passion of the fan base is a large part of the story of the show Fringe."

The actor recalled he was involved in the initial conversations for Season 5 "to a greater extent than at any time in the prior seasons of the show," noting series producer J.H. Wyman's willingness to be open with the cast about the direction of their characters.

"He gave, I think all of us, the signposts of what our season would be in a way that hadn't happened before. He gave us all the opportunity to plot out how we thought we should be playing all our individual characters. From that standpoint, it was tremendously satisfying. The Peter-as-Observer arc was quite interesting this year. Always to me what was interesting about Fringe was that even though the larger story was as big as it could possibly be, the beating heart of the story was always the family tale. I really enjoyed the fact that what was at the center of driving Peter and Olivia this year was both the recovery and the loss of their child, and then as a couple trying to grapple with that both individually and together. I think we did a good job this year of having the larger story driving forward, but having the interpersonal story being honest. As always, Peter and Walter are inextricably linked, so Peter mirrored all the mistakes his father had made all those years ago regarding Peter, regarding his own daughter. So yes, I thought it was a very satisfying story and a proper way to see our story end when you see the finale tonight."

Jackson has portrayed the role of Peter Bishop since the series' beginning five years ago, and he believes the finale brings a fitting end for the character. He credits Wyman with accomplishing the difficult task of tying together not only the final mysteries of the series, but bringing a suitable conclusion to the characters as well.

"The proper ending for Peter that we've known on screen for the past five years actually happens tonight. I really love the ending," Jackson said. "I think it makes really good sense and it wraps up his story in a way that is, of course, intertwined with all the characters around him, but specifically intertwined with Olivia and with Walter and with Etta. I think it is a proper ending to the person and the story we've been watching for the last five years. I feel that way for all the big three -- for Olivia, Walter and Peter. Olivia and Peter end in the proper place, Olivia, Peter and Walter end in the proper place; Peter and Walter get to the place where they need to be. For our story, it ends tonight. The beauty of what Wyman has done is that he allows the space for people to live on with these characters should they desire to."

For the final season, Jackson noted he was most interested in seeing the conclusion not only for his character, but Peter's entire family -- including his father Walter (played by John Noble) and his wife Olivia.

"Neither Wyman nor myself were interested in having another season of Peter and Olivia will they or won't they," he said. "It was more interesting for them to still be a couple, still a married unit, but one that was deeply, deeply damaged by the loss of their child and to have Peter mirror the mistakes that Walter had made. The becoming an observer portion of it was just a natural outcropping of Walter's great sin was breaking the universe to save his child because there was no place that was too far for him to go. In the version of the story that we were telling, the most outrageous thing that Peter could do would be to become the enemy that destroyed him. I thought that was actually a fairly natural outcropping and also gives Peter and Olivia an interesting arc to their story as they tried to figure out how to be together again, instead of being alone together -- to try and figure out how to make their marriage kick again with the loss of their child."

The Fringe finale isn't Jackson's first series-ending episode: The actor also experienced the finale of the teen drama Dawson's Creek 10 years earlier. While Fringe and Dawson's Creek are undeniably in different genres, Jackson noted there are actually quite a few similarities between the two experiences.

"Clearly, I am a decade, maybe even more, older than we were when we finished Dawson, but I've had now the good luck on both the TV shows I've worked on that we've known going into the last season that it was the last season," he said. "It gives you an opportunity on set to properly say goodbye to the people you're working with and it also has a really good way of focusing the mind on trying to make sure no matter how hard it is, no matter how tired you are, that you give everything you have to those last shows because there is no tomorrow. You want to make sure you go out on the highest note possible. The feeling on set both times was quite similar. There's an almost carnival-like feeling as you get toward the end of this huge experience in anybody's life and it's a very cathartic thing. At the very end, you look around at this group of people who you've spent seventy hours a week with for nine months out of the year for the last four or five years and you have a chance to just take stock and go, 'My God, I can't believe that we did this.' At the same time, creatively, because you know it's the end, you have the opportunity to finish it on your own terms, which is not often the case in television.

"The differences are that Dawson's Creek was never -- I was never a fan of 90210, it wasn't my genre of show," Jackson continued. "Fringe, on the other hand, is right up my alley. I have more of a personal stake in the climax of this show and making sure that it is the satisfactory end to the journey the audience has been on. I hope we achieve that tonight."

Although Jackson is far away enough from Dawson's Creek to determine what the takeaways were as an actor, he's only one month out from wrapping Fringe. But that doesn't keep him from determining what was most satisfying about the experience.

"I can tell you the thing that is most satisfying to me as an actor is the work that John and I did with Jeff Pinkner and Joel Wyman to try and keep the father/son relationship as honest and dynamic as we could in the center of a very, very large crazy science fiction story," he said. "That was always a point of focus for me. I think having the chance to be on a serialized TV show and to tell my piece of it, which was the story of the prodigal son who starts off doing everything he can to get out of this world and eventually gets drawn in to the love of his father and falls in love with a woman and over the course of the seasons, completely reverses his desires to become a really dedicated son and a solid, reliable boyfriend and then husband, to a crazily protective father -- I think that's a really interesting journey to go on. I think the Walter and Peter stories nearing each other so distinctly in the fifth season is an interesting thing. As an audience member, I'm most engaged by serialized storytelling, so I guess as an actor, the thing that I take away from it is how much fun it is to perform a serialized story."

Looking forward, Jackson is hopeful the show will prove an example of what the afterlife of shows with a cult following are like in the modern era of the Internet and the new way that television and its viewers have come to work.

"Part of what made the audience of [Firefly and Star Trek] so passionate was scarcity. It was hard -- less so for Firefly, particularly for Star Trek -- but it was hard for fans, the community of those shows, to find them, disseminate them, talk about them because, as hard as it was for us to remember, Firefly was, not at the very beginning, but long before the ubiquitous nature of the Internet and fan forums and things like that," he said. "Fringe in an odd way started its afterlife while it was on the air. The community of the show is currently strong and vibrant. I have a funny feeling that the afterlife of this show, much as we who have been making it the last five years are finishing our portion of it, I think it will live on in that community. How it will manifest itself, I don't know -- perhaps there would be a movie. I think there will probably be a lot of fan fiction. Maybe there will be maybe even some filmed addendum to the show or televised or podcast -- however it manifests itself. I feel like the afterlife of Fringe is a test case for how modern shows will live on after they go off the air."

The Fringe finale airs tonight at 8 ET/PT on Fox.