The two play infamous literary lovers Cathy and Heathcliff in the latest adaptation of Emily Brontë's classic novel.
And its themes of passion and obsession seem to have been echoed off camera too - with both stars indicating a close bond while promoting the film.
Wuthering Heights is the latest in a string of films where it's been suggested romance rumours were used as promo: think Sydney Sweeney and Glen Powell in Anyone But You, and Lady Gaga and Bradley Cooper in A Star is Born.
Robbie and Elordi may have successfully got us talking, but some fans have been left less than impressed with their behaviour, with one telling BBC News it gave her "the ick", and another calling the display "weird and tacky".
Some also suspect the actors' gushing words about each other may be just another cog in the film's PR machine, especially given Robbie's husband, Tom Ackerley, is one of its producers.
So have the stars' supposedly intimate moments been designed to generate romance rumours (and social media buzz) around a movie some critics were less than glowing about? And has it worked?
A 'mutual obsession'
Warner BrosLet's start with what exactly Robbie and Elordi have said and done.
Throughout the press tour for Emerald Fennell's hotly anticipated film, the two Aussie A-listers have been dishing out viral quotes.
In January, Robbie told Fandango that when her co-star wasn't close by, "I felt quite lost like a kid without their blanket or something". In the same interview, Elordi confessed he and Robbie had "a mutual obsession", adding: "I was enamoured by her."