The show opened with McCarthy and husband Ben Falcone at their "day job," with each dressed as one of the random characters tourists pay to take photos with on Hollywood Boulevard.
"Don't tickle me, I'm not that kind of Elmo," McCarthy exclaimed while dressed as the Sesame Street character, before getting a call from Kimmel's people asking if she could hurry up and get to her dressing room.
"Yeah, this place sucks anyway, my Spanx are like a swamp!" she joked, before running inside.
Her Monologue and Game with Her Parents
McCarthy hit the stage dressed as a Christmas tree and would end up swearing a number of holiday-inspired costumes all night long, after being told by Kimmel that everyone would be similarly dressed. They weren't. The night saw her changing into a menorah outfit, gingerbread man and giant candy cane.
She then wheeled out her parents for a game called "Who Loves Their Daughter More?", where the two were tasked with answering questions they should know about their child.
Jennifer Aniston and Melissa Mock Climate Change Deniers
In a segment aimed at those who deny the existence of climate change and its effects on the environment, McCarthy took time to question another scientifically proven issue facing the planet: gravity.
As she argued why the theory of gravitation is clearly fake, Jennifer Aniston swung by to try and set her straight. It didn't work.
The sketch ended with the "Friends" star flying around on a harness while McCarthy cracked, "I guess your SmartWater didn't work."
Melissa's Tommy Wiseau Story
Dave Franco, dressed in a reindeer costume, also stopped by to promote his new movie, "The Disaster Artist," which offers a look into the totally bizarre story behind the making of the film "The Room." The movie from star/director/writer Tommy Wiseau became a cult classic, with Wiseau himself becoming famous for his many eccentricities.
During the interview, McCarthy shared her own, totally random, experience with Wiseau back in the day. According to her, he showed up at her door one day selling copies of the movie -- and she purchased one! She says she was moved by his pitch, despite looking like a total vampire.
McCarthy and Octavia Spencer apparently longtime friends and also appeared in a Weird Al sketch together back in the day.
"I knew you pre pre pre anything, do people always ask why don't you to work together more? I get that a lot, we want to, but we have," McCarthy explained, before setting up a clip from the comedian's short-lived comedy show.
The clip showed them both asking Yankovich questions as random people the camera crew caught on the street.