Entertainment

WATCH: Jimmy Fallon and Zach Galifianakis switch spots

The host became the guest, and the guest became the host, and the guest made fun of himself in the process.

Zach Galifianakis swapped roles with late-night host Jimmy Fallon during last night’s episode of “Late Night with Jimmy Fallon,” for a humorous, if not awkward, conversation about Galifianakis’s new movie, “The Campaign.”

The segment opened with Zach sitting at the anchor desk, introducing himself … at which point Fallon approached the stage and sat in the guest seat.

Fallon didn’t take long to criticize his fill-in’s interview talents.

“So, how was your flight?” Galifianakis asked.

“Really?” Fallon snapped. “That’s your first question?”

The conversation shifted to Galifianakis’s new project.

“So, tell me about this movie,” Galifianakis said. “What was it like working on …” at which point he paused and ruffled his script, trying to remember the movie title.

“The Campaign?” Fallon responded.

Galifianakis leaned in and whispered: “This is late Night With Jimmy Fallon, and I’m Jimmy Fallon. Don’t mess around with this.”

Then the ‘host,’ channeling the ill-informed critic persona from his “Between Two Ferns” web series, delved into a question about celebrity interactions.

“ I love celebrities,” he said. “They’re never wrong about anything … what was it like to work with Will Smith? Was that fun, working with Will Smith?”

“I think you mean Will Ferrell,” Fallon said. “Will Smith wasn’t in this movie.”

“Aw, that must be a disappointment.”

Galifianakis wasn’t above a good weight joke (about himself), telling Fallon, “I’ve noticed that you gain weight for every role, but then you don’t lose it after, so you just keep getting fatter.”

“Is that a question?” Fallon asked.

“No, I guess not.”

“The Campaign,” which depicts the rivalry between two North Carolina politicians, opens Aug. 10.