Wait, Does Diane Keaton Play Justin Bieber's Dead Grandma in His Latest Music Video?

Justin Bieber's "Ghost" music video is premiering tomorrow, and he has one very special guest star: the Diane Keaton. And the sneak peek that they both shared to Instagram looks so sweet and dandy and wholesome ... until we stopped to ask ourselves: Wait, is Diane Keaton supposed to be Justin's dead grandma?

In the preview, we see an adorable montage of the two global stars laughing and dancing together, hugging, and taking in views of the ocean with the lyrics from Bieber's song setting the bittersweet scene: "And if you can't be next to me/Your memory is ecstasy/I miss you more than life." Which leads us to believe that our melancholy hypothesis is accurate, and Bieber is reminiscing on beautiful memories he once shared with his grandma, a.k.a. Diane Keaton.

Both Diane and Justin shared the clip from the touching video on Instagram. While Justin opted for no caption, Keaton used hers as an outlet to express her enthusiasm over working with the Biebs. "AM I DREAMING???," she wrote. "WHAT AN HONOR IT WAS TO WORK WITH JUSTIN BIEBER AND HIS INCREDIBLE TEAM!!!" With all due respect, Ms. Keaton, we'd assume that it was really the honor to work with you. The video, which will premiere tomorrow, Friday, Oct. 8, is directed by music video and film producer Colin Tilley.

And of course, in several shots of the preview, the actress wears her signature hat, channeling her character Erica from the 2003 film Something's Gotta Give. So ... is Justin Erica's grandson? Guess we'll have to wait until tomorrow to find out.