Safran told E! Online that Blair (Leighton Meester) will be caught between Chuck (Ed Westwick), Louis (Hugo Becker) and Dan (Penn Badgley).
"What I said at the top of the season was this was pretty much going to be a romantic love triangle between Chuck, Louis and Blair and that Dan was going to be more a friend of Blair," he said.
"This second half of the season, that triangle absolutely becomes a square in a major way. That is where that story is going."
Safran also defended the "good struggles" the writers have given Chuck and Blair, saying: "It's like just when they think they've conquered one aspect that was keeping them apart, another one pops up. I believe that is always going to be Chuck and Blair's issue with each other.
"They just can't seem to get it right. The thing is, can Chuck and Blair ever be in a place where they can meet each other eye to eye or will one always be a few steps ahead of the other? That's never boring to me."
Safran added that Dan and Serena (Blake Lively) will continue to pretend to be dating after they made up a relationship to protect Blair in last night's episode.
He explained that the fake romance "starts out meaning more to Serena" but hinted that Dan could fall for her again, saying: "You'll have to watch and see. Old patterns die hard!"
Gossip Girl airs on Mondays at 8/7c on The CW.
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