Ryan Reynolds introduces himself as the star of IF, and Park introduces himself as Krasinski, the writer-director of the forthcoming movie, much to Reynolds' annoyance.
"You're not John Krasinski!" he fumes. "John Krasinski is much shorter and less Asian than you."
Park replies, "Uh, Ryan, I know it's been a while since we shot, but we spent like four months together, like 10 hour days."
Reynolds starts asking Park questions like who he's married to. "Emily Blunt," Park replies, to which Reynolds accuses him of using Wikipedia to find out about the former Office star's biography.
Park then reveals a sneak peek of IF will debut during the Super Bowl, and they show a behind-the-scenes look at the film. The footage even shows Park in a director's chair, continuing the Krasinski replacement gag.
Co-producer and star Reynolds explains the project, which he likens to a "live-action Pixar film," has been in the works with Krasinski "for years."
It centers on a girl named Bea who is going through a rough patch in her life, and "as a coping mechanism, she starts to see every single person's imaginary friend," Park-as-Krasinski continues.
The behind-the-scenes video also shows the voice star behind one of the IFs — or Imaginary Friends — The Office's Steve Carell.
Reynolds continues, "It's about that friend who's there for them, unconditionally and always."
IF debuts in theaters May 17 from Paramount Pictures.