Warning: This article contains spoilers for the season 2 finale of And Just Like That, "The Last Supper Part Two: Entreé."
In the episode, Cattrall's character Samantha Jones, who is now living in London, makes a brief appearance when she calls her pal Carrie Bradshaw (Sarah Jessica Parker) to apologize for not being able to attend her last big apartment party — and pay her respects to the brownstone unit: "Thank you for everything," she says over phone. "You f---ing fabulous, fabulous flat."
At the end of their chat, Samantha hangs up and kisses her phone — a move that writer, director, and executive producer Michael Patrick King said was not included in the episode's original script.
"Then the phone call's over and something amazing happens after they say goodbye," King revealed on the And Just Like That… The Writers Room podcast, "which is Samantha kisses the phone."
"Which was, by the way, not in the script," one of his cohosts added.
"Not in the script," King agreed. "It's just totally a moment of an actor playing the moment and it's really nice."
Max Kim Cattrall returns as Samantha Jones in the 'And Just Like That' season 2 finale
News of Cattrall's surprise appearance on the Max series was leaked before its second season could even air, ruining King's original dream to create a surprise, brain-melting scene for longtime Sex and the City fans.
"My goal, for us, was to have Carrie pick up her phone and look at it, see the word Samantha, and have the audience's head blow off," King said earlier in the episode. "When it comes around the sentimentality of something called 'The Last Supper,' it's hard to not imagine that Samantha would've gotten a call from Charlotte [Kristin Davis] and Miranda [Cynthia Nixon] saying, 'Hey, Carrie's doing the last supper and this time it's real. She's leaving this apartment.'"
While the cameo was undoubtedly a momentous occasion for fans who are aware of Cattrall's complex relationship with Parker and her previous refusal to star in a third Sex and the City movie, King explained that within the Sex and the City universe, it was pretty par for the course considering its core four characters are still very close friends.
"In my multiverse of And Just Like That [and] Sex and the City, they were always talking. Always!" King said. "Texting and talking — and not just Carrie, but Samantha and Miranda and Charlotte."
Parker recently told EW that she thought it was a "really nice idea" for Cattrall to return for the finale.
"It's a really opportune moment in the story, [a] consequential event happening in Carrie's life, that Samantha rings and they have this quick, lovely, sentimental, funny call," she said at the time. "And it just feels normal and really nice, and I'm glad that we could manage it and work it out and get it sorted time-wise and schedule-wise."
Added Davis, "We had a conversation about it and we decided that it was right for the fans. The fans miss Samantha. The fans love Samantha. Samantha's a fantastic character. We get it."
Listen to King discuss the ad-libbed moment in the podcast above.
Sign up for Entertainment Weekly's free daily newsletter to get breaking TV news, exclusive first looks, recaps, reviews, interviews with your favorite stars, and more.