Along with Steve Martin and Alec Baldwin, Melissa McCarthy is one of those performers who’s been on “Saturday Night Live” so many times, as a host or making extremely memorable guest appearances, that it’s easy to forget she wasn’t an actual cast member.

McCarthy sure could have been, as she demonstrated again in her sixth time as host, where she showed off her incredible commitment to comedic bits. She has a knack for heightening moments and introducing characters that range from sad, weird loners to shifty and overconfident schemers. Even when McCarthy is simply portraying a heightened version of herself, as in this episode’s monologue, she’s apt to fling herself over a piano bench or introduce a new talent, namely “mouth horn” (more on that in a bit).

As reliable a comic force as McCarthy can be, she can still be held back by weak writing, as has happened a few times in past appearances. In this episode, she benefited from coming off a strong cold open featuring Colin Jost as aggressive Defense Secretary Pete Hegseth and a funny monologue to launch into a trio of sketches that were as great as any she’s done on the show before, despite a few instances of her microphone sounding muffled.

She played a clingy woman who latches on to a supermarket worker (Jeremy Culhane) handing out cheese samples, a seemingly friendly elderly neighbor who goes to extremes to show her friendship to a 12-year-old boy, and a terrible UPS employee caught misbehaving on someone’s doorbell camera.

Things got a little bumpier after “Weekend Update” with sketches that pushed McCarthy back to supporting roles, like one that featured Andrew Dismukes as an overly sensitive Sunday supper host and one about moms who play truth or dare for the first time (it gets sexual very quickly). These were fine, but didn’t take advantage of McCarthy’s skills as much and felt like they could have been done any other week.

Later on, things improved when McCarthy played the mayor of Cousin Planet in a very silly music video from Jane Wickline and Veronika Slowikowska, and one half of a New York City couple (with Bowen Yang) showing off their kitschy holiday decorations for Spectrum News NY1.

McCarthy is a comedic national treasure and when she’s allowed to fire on all cylinders on “SNL,” as she was in a few of the night’s sketches, there’s nothing like it.

Musical guest Dijon performed “HIGHER!” and “Baby!/Another Baby!” Before the goodbyes, a title card honored Craig Kellem, a producer on the first season of “Saturday Night Live” who died this week.

This week’s cold open brought back Jost as Hegseth in a White House press conference. Jost played him as a petulant, energy drink-chugging bully, who starts by asking the assembled reporters, “Where are the fatties?” Referencing the U.S. attacks on sea vessels in Venezuela, he told the reporters, “Pretend I’m a random fishing boat and fire away.” Matt Gaetz (Sarah Sherman) was among the reporters, showing up to ask if the U.S. was intercepting all illegal things being transported across borders, or just drugs. Hegseth made pop culture references in his responses, including invoking “6-7” and singing some of the famous “Animaniacs” nations of the world song. A sleepy President Trump (James Austin Johnson) seated near Hegseth woke up from a sexy dream about New York mayor-elect Zohran Mamdani to remind us that the “fog of war” only comes up when people are trying to hide war crimes before napping again. “We gotta get him to another MRI before he wakes up,” Hegseth said.

In her monologue, McCarthy kicked off Christmas season on “SNL” by showing off her talent for “mouth horn,” a kind of humming/blowing/beatboxing of songs like “Carol of the Bells.” She got a lot of snow dumped on her and fought with cast member Marcello Hernández as he tried to move a piano across the stage. Dejected, McCarthy was joined by Kenan Thompson, whom she called “Santa Kenan” before cast members came on stage to close it out with “Christmas (Baby Please Come Home)” with McCarthy mouth horning the song.

Best sketch of the night: Firing of the worst UPS employee is USPS’s gain

McCarthy plays Donna, a UPS delivery driver who has been hurling packages on a customer’s porch, opening up boxes and even squatting to relieve herself until it’s dark, all revealed in a series of security videos. Donna’s denials, her attempts to scoot out of the meeting with UPS managers (Mikey Day and Ashley Padilla), her fake fainting and her tenacity in chewing on paper while Day tries to pull it from her mouth were all excellent. So much so that Day, who has worked with McCarthy since her days at The Groundlings, starts to break character and hold back laughs, something extremely rare for him.

Also good: Cousins don’t even exist in July

You could make a strong argument that the video about the vengeful elderly woman and the supermarket sketches were better showcases for McCarthy, but there’s something catchy and true about this low-fi video that considers where cousins go when you don’t see them during the holidays. It turns out they live on Cousin Planet where family secrets are revealed and every conversation is catching up. The first rule is that cousins shouldn’t hook up, but the second rule is that the first rule is flexible. This video is funny, weird and a great showcase for featured players Wickline and Slowikowska.

‘Weekend Update’ winner: That’s it, drunk raccoon, you’re cut off

Ben Sherman was entertaining as Lance, a redhead who was badly sunburned on vacation (he even brought a ginger boys’ choir), but it was tough to top Sarah Sherman’s all-over-the-desk portrayal of the drunk racoon that went viral after being found passed out in a Virginia liquor store. Sherman asked “Update” co-presenter Jost if they’d hooked up the night before and kept propositioning him (“I’ll ride your head like a Davy Crockett hat”) while also abusing him (“Quiet, piggy!”). The guest bit benefited from a nice use of cuts to black and white to show Sherman as a raccoon caught on a Ring camera.