Don't let holiday spirit blind you to the monster next door, advises Kate McKinnon and SNL

With the holiday season in full, carefully manufactured swing, we’ve all been inundated by those Christmas commercials about showing goodwill to our fellow humans. Last night’s Billie Eilish-hosted (and musical guested) Saturday Night Live, however, provided a darkly funny counterpoint to the idea that throwing your doors open to strangers in the spirit of giving guarantees a movie-worthy feel-good biopic. Sometimes, the short film “Lonely Christmas” posits, that sweet but bereft-looking old lady across the alley is actually a creepy weirdo with a whole lot of genuinely horrifying secrets in her closet.

Parodying those carefully focus-grouped commercials where the holiday spirit prompts young people to, say, help that nice old lady with her groceries (sometimes, you get mittens!), the short sees teen Eilish spotting Kate McKinnon’s solitary widow through her lit window, sighing and staring wistfully at her husband’s photo. Breaking out the markers and notebook paper, the two strangers quickly strike up a friendship, as Eilish’s well-intentioned teenager informs her unseen mother that they’re having one extra for Christmas dinner.

So far, so heartwarming, right? And, sure, the senior citizen does hold up a card asking if there are going to be any Black people or Jews in attendance, but that doesn’t necessarily mean anything, right? (“Could you check?,” the smiling woman urges Eilish’s teen to make sure about the whole “Jews” situation.) With hilarious escalation, things go very much downhill from there, as Eilish finds, to her increasing unease, that she’s invited a stranger to her home who also loves Donald Trump, hates her family (who voted for that “disgraceful” woman instead), is deliberately sickening her own adult son with hypodermics full of green liquid to keep him under her thumb, and, yeah, probably murdered that husband whose picture she was staring at.

With McKinnon (back on the show after missing the season’s first seven episodes filming the Tiger King miniseries) portraying the outwardly harmless old woman, the sketch is powered by pure, glassy-eyed madness, revealed in escalating, Love, Actually-style cue cards. If there’s a lesson to be learned, it’s that dangerous weirdos are still dangerous and weird, even at holiday time. She sees you when you’re sleeping.