Beware of radical "moose" "lambs," guys.

"Saturday Night Live" this weekend to add a glorious new impression to her repertoire. Kristen Stewart hosted the February 4th "SNL" but -- in an inspired choice -- McCarthy was cast in a guest role as White House press secretary Sean Spicer. Her angry, press-hating, truth-avoiding Spicer became an instant classic, arguably up there with Alec Baldwin's Donald Trump, Larry David's Bernie Sanders, Kate McKinnon's Hillary Clinton, Will Ferrell's George W. Bush, and ... Tina Fey's Sarah Palin? Is it too soon to rate this impression to Palin levels?

The real Sean Spicer reacted to the sketch, once someone sent him a link to it, and he didn't rip on it (like his boss would), although he didn't want to spend a lot of time talking about it. (See video below.)

The press briefing sketch went on for eight minutes of pure hilarity, with McCarthy not even seeming to rely on cue cards for the jokes.

"Before we begin, I need you to know that myself and the press have gotten off to a rocky start. When I say 'rocky start,' I mean it in the sense of 'Rocky' the movie because I came out here to punch you in the face. And also I don't talk so good. Now I'd like to begin today by apologizing on behalf of you to me for how you have treated me these last two weeks, and that apology is not accepted. Because I'm not here to be your buddy. I'm here to swallow gum and I'm here to take names."

Watch the video:McCarthy got herself trending on Twitter Sunday morning for her brilliant performance. Hopefully this is just the first of many Spicer impressions to come.

When asked for reaction, Sean Spicer called the sketch "cute" and "funny" ... even if it's hard to believe he really meant it:

Spicer did give McCarthy some notes for next time, via Extra: Dial it down a bit, and stop chewing so much gum. And, for the record, he's standing by his man on Alec Baldwin's "mean" Trump impression.

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