The Princess of Wales gently tapping her husband Prince William on the bottom as they walked the BAFTAs red carpet appeared to be a rare show of PDA.
But a lip reader has revealed what he believes was said between the couple before Kate carried out the cheeky gesture - and it might not have been quite the affectionate gesture it first seemed.
In a clip showing the lead-up to and the bottom patting moment, William and Kate can be seen making their way along the red carpet.
At the beginning of the footage, something appears to grab Kate's attention as she dramatically turns her head to see what is going on behind her.
As she turns back to William who didn't turn around and is instead just facing ahead, they appear to exchange words.
And according to lip-reading expert Jeremy Freeman, Kate appears to say to William: "How did you miss that?"
Jeremy tells the Mirror that William replied by saying: "What?" before Kate adds: "Stop ignoring" - although it can't be made out who she tells him to stop ignoring.
And William replies by saying: "Ignoring who?" before Kate carries out the cheeky bum pat.
The lip reader's findings also come after a body language expert said she believed the tap was like a "sexy reprimand".
Expert Judi James explained "As they walk past the crowds, Kate seems to look back to acknowledge a complimentary comment with a smile. She then pushes her right hand out towards William’s in what looks like a cue to hold hands.=
"William mistakenly leans in to suggest he is expecting more of the flirty whispering they have been doing and raises his hand as his head gets closer, missing Kate’s offer.
"Kate then 'rewards' William with a pat on the bum. So this works as both a sexy ritual or appreciation and a small reprimand for missing her cue."
During their night at the BAFTAs last night, the couple met Bafta chairman Krishnendu Majumdar, chief executive Jane Millichip and chairwoman of the Bafta film committee Anna Higgs ahead of the ceremony.
William told the leaders they were doing a "great job" and nodded as Ms Higgs spoke of how important it was to pursue "diversity" in the industry.
He praised Ms Millichip for handling her position well despite being made chief executive in a "baptism of fire ".
The last Bafta ceremony the prince and princess attended was three years ago, with the 2021 event postponed due to complications related to the pandemic.
During the ceremony, a pre-recorded tribute to the late Queen was paid by Dame Helen Mirren, who played the late monarch in the 2006 biopic The Queen.
William and Kate watched from the centre of the front row as Dame Helen said: "Cinema at its best does what Her Majesty did effortlessly – bring us together and unite us through a story.
"Your Majesty, you were our nation’s leading star."
