Joel Wyman told Give Me My Remote that fan speculation has not come close to predicting the events of the episode.
"In season three, [the show] was all about self-actualisation where each character was starting to come to terms with who they are," he explained. "Season four will be altogether different because the end of the season will definitely point you in a [new] direction."
He added: "I haven't heard anybody on any website [give] a hypothetical to come even close [to] where we even are. We like that just fine."
Co-producer Jeff Pinkner added that he and Wyman are not worried about fan reaction to the finale, which airs on May 6.
"We're not feeling so much pressure at this point because we know what [the episode] is and we think it will work in all those ways," he insisted. "It will indicate what season four is going to be [about] in hopefully a way [that] people will be really excited about."
Fringe will return to Fox on April 15.
> The past and future of Fringe