The pair, played by Sarah Jessica Parker and Chris Noth, were kissing passionately while shooting on the streets of New York.
Catching a lift: Mr Big sweeps Carrie off her feet during filming in New York yesterday
The scenes are the latest in a host of dramatic moments, which include the couple's wedding - and a huge argument. Not all scenes will make it into the final movie.
As interest in the film reaches fever pitch, star Chris Noth says it's the only topic of conversation people want to discuss.
He told the New York Post: "Can't talk about Sex and the City. Everybody only wants to talk Sex and the City!"
Passion: Mr Big and Carrie's relationship is set to get steamy
He continued: "Bystanders text-message from our locations. Extras leak to the press what's shot. To keep the plot points secret, the show's filming false scenes and fake endings just to throw everybody off."
Noth has revealed how the fascination with the project is even taking over his other projects.
He explains: "You want to know about Sex and the City? I'm shooting outdoors in a bad neighbourhood in The Bronx for my other show, 'Law & Order.' We're tying up traffic. A held-up trucker behind me is crazed.
Back together: Chris Noth and Sarah Jessica Parker will reunite onscreen
He tears through the light, halts our shoot and climbs out of his big 10-wheeler. I figure he'll pull a gun and shout: 'Get the f--- out of here you piece of s---,' and he rushes to me with, 'When you going to marry Carrie?'"
Meanwhile, Oscar winning actor Russell Crowe has revealed how he dreamed of landed a part in the popular series.
He has said: "I would have loved to do a guest [appearance] on 'Sex and the City.' That's my wife's favourite show."
"I would have loved a turn on an episode where my wife wasn't expecting me to be there. That would have been fun."
The movie is set to hit screens in next year.
