Watch Melissa McCarthy Debate the Existence of Gravity With Jennifer Aniston

Filling in for Jimmy Kimmel, McCarthy promised the audience she would address a subject "the mainstream media doesn't want you to hear about."

Melissa McCarthy is no stranger to playing zany characters — she was a scientist who believed in ghosts in Ghostbusters and Sean Spicer on Saturday Night Live, after all. But as the comedian was filling in as guest host for Jimmy Kimmel on Jimmy Kimmel Live! on Thursday night, she might have played her strangest character yet: a conspiracy theorist who doesn’t believe in gravity.

Telling the audience that the mainstream media is hiding the truth behind the theory of "gravitivity," McCarthy argues that the theory's originator, Sir Isaac Newton, also created the Fig Newtons cookie brand. Jennifer Aniston interrupts her lecture to remind her that people cannot fly, only to be forced into a harness by McCarthy and raised into the air so that the conspiracy theorist can prove her point.

McCarthy filled in on Thursday night for Kimmel after his son had heart surgery. Other guest hosts this week have included Chris Pratt, Tracee Ellis Ross and Neil Patrick Harris.

Check out the full segment below.