Speaking to TV Line, Stephanie Savage and Josh Safran explained that the episode will be lighter than last season's closer.
"Last year's finale was a little bit darker," Savage said. "And this one is more juicy and fun. Every finale is a game-changer, but this one really is spinning everyone off in new ways that will be apparent as you watch it."
Safran added: "The road map for all of the characters will be very clear... That's not to say there won't be multiple cliffhangers."
The duo also revealed that Chuck (Ed Westwick) will investigate his father's involvement in the death of Raina's mother, adding that he gets "very, very dark".
Meanwhile, Savage teased that Blair (Leighton Meester) will be torn between a romance with Dan (Penn Badgley), Chuck or Prince Louis (Hugo Becker).
"That story keeps building right up until the finale episode," she said. "The last two episodes [of the season] are actually a two-parter that all takes place during the course of one night."
Gossip Girl returns with a new episode on Monday, April 18 at 9/8c on The CW in the US and on Wednesday, April 20 at 8pm on ITV2 in the UK.
> Ethan Peck 'lands Gossip Girl role'
Watch the trailer for the next episode of Gossip Girl below: