Kate Winslet's been replaced.
Leonardo DiCaprio recreated one of the most famous moments from "Titanic" during a surprise appearance on "Saturday Night Live" last night -- with Jonah Hill playing Rose.
It all went down during Hill's opening monologue, which began with him talking smack about his "Wolf of Wall Street" costar.
Then, about midway through, Leo popped out -- and was welcomed with a big round of applause and screams from the audience.
Check out the video above to see what prompted the "Titanic" role playing.
It's been 17 years since the film was released into theaters -- and we just love seeing Leo step back into Jack's shoes, even for a brief moment!