Speculations of romance ran wild after movie fans saw a red carpet photo of actress Jessica Chastain being lovingly kissed on her arm by Oscar Isaac, with whom she costars in the new HBO limited series, Scenes From a Marriage.

And when Chastain finally addressed the buzz surrounding the kiss from her costar, fans lost their minds.

But first, we need to examine the kiss on the red carpet at the 2021 Venice Film Festival, which took place on September 4.

The gentle display of affection hinted at what viewers could expect when watching the new show, which is a modern adaptation of Ingmar Bergman's Swedish series of the same name from 1973.

But let's set the record straight.

Both actors, who have known each other for two decades and have now twice played each other's wife and husband, are respectively married in real life.

Chastain's husband is fashion executive Gian Luca Passi de Preposulo and Isaac's wife is screenwriter and director Elvira Lind.

But who can blame fans for losing their minds over the red carpet kiss?

Whether or not the sultry moment was a marketing ploy, the romantic chemistry is palpable.

Just look at the passion oozing from Isaac's eyes in this slo-mo clip.

Many fans wondered if there was something going on between the actors off-camera.

Chastain finally addressed the viral hubbub simply by teasing fans with a photo of The Addams Family's Gomez Addams kissing Morticia Addams's arm.

In the tweet's caption, she included a smiling devil emoji and wrote "Sept 12th," indicating the release date for Scenes From a Marriage.

She's a sly one, that Jessica.

When comedian/actress Mindy Kaling asked Chastain on Instagram, "Why is Oscar Isaac the only person allowed to kiss your inner arm," Chastain coyly responded:

"Don't hate lol."

Their back-and-forth was screengrabbed and shared on IG by, @commentsbycelebs.

So cheeky, so brilliant.

Now that she has spoken, the swooning continued on Twitter.

Chastain and Isaac have been friends since attending Julliard together over twenty years ago.

They previously played husband and wife in 2014's A Most Violent Year.

At the Venice Film Festival, the Zero Dark Thirty actress told the press that working together with Isaac was "both a blessing and a curse," because "We got to the point where we were reading each other's minds, and I was like, 'Get out of my head!'"

She joked, "I felt on this job there was no quiet time."

In a 2014 interview with USA Today, Isaac said of their professional sympatico:

"The fact that we can tell each other whatever we wanted, that we could argue, we're very free. We approach things in a very similar way."

If the steamy red carpet kiss was a PR stunt for their new show, it appears to be working.

Here is a trailer for Scenes From a Marriage.

Scenes from a Marriage (2021) | Official Trailer | HBO youtu.be

The show—written, directed, and executive produced by Hagai Levi—is described on HBO's website as one that:

"re-examines the dilemmas probed by the original, exploring love, hatred, desire, monogamy, marriage, and divorce through the lens of a contemporary American couple."