“Saturday Night Live” returned after a monthlong hiatus Saturday with a familiar face, a familiar cold open and a familiar impersonation. Guesses who and what?

Alec Baldwin brought his Donald Trump back to “SNL” with a quick reference to a current event — “what a difference 59 Tomahawks can make” — and a much longer riff on a less current one (coal).

Then, a surprise: Baldwin channeled Bill O’Reilly late in the program in a rip of “The O’Reilly Factor” and its host, who is embroiled in a New York Times-reported controversy over settlement payments to former Fox News employees and contributors. Then, the next surprise: In a split screen, Baldwin played O’Reilly on one side, and Trump on the other.

“Good evening Bill,” said Trump/Baldwin. “So wonderful to be here on the Factor. I’m a big fan.”

O’Reilly/Baldwin: “Can I say, Mr. President, you look even better on TV.”

Trump/Baldwin: “Can I tell you, I see a lot of myself in you, Bill.”

Yet another surprise: Baldwin’s O’Reilly impression was amusing.

Baldwin — whose memoir “Nevertheless” was released Tuesday — crossed over into questionable (which is to say raunchy) territory with the “Factor” segment, which aired about 12:30. It had bite.

By contrast, the cold open was dead on arrival. It worked familiar territory — campaign promises written in sand, or in this instance, written in coal dust. But as cold opens go, this one was so innocuous that even Trump supporters would not have been offended.

Baldwin’s Trump was at a fictional rally in Union, Kentucky, fielding fictional questions from real “SNL” cast members — playing his working class voters — about their prospects.

Trump/Baldwin: “God, I love coal. You guys have suffered terribly. I will do everything I can to make sure you people work in coal the rest of your lives.” Asked whether there might be other employment opportunities, he responded: “Sorry, hombre, it’s all coal.”

“In my America,” he said of employment, “it’s coal mines and Goldman Sachs.”

He was asked about the failure of his plan to replace Obamacare . . . “You mean Paul Ryan. I did everything I could.”

Asked about relocation, he responded, “My wife doesn’t want to move either . . . wives can be crazy.”

Reaffirming the support of those who voted for him: “You people stand by me. It’s like you found a finger in your chili, but you still eat it.”

“Weekend Update” followed after midnight, with a little more (umm) bite. Colin Jost: “The only scarier thing than Donald Trump acting not presidential is Donald Trump acting presidential.” Conflating the Tomahawk strike on the Syrian airfield with Trump’s Twitter habits, “when he’s angry he hits send.” Michael Che offered an explanation of the situation in Syria, then cued the clip — of Larry, Curly and Moe.

Bottom line: Don’t take off four weeks again, “SNL.” The world’s moving too fast, and jokes have a way of getting stale fast too. (At least “The O’Reilly Factor” segment managed to be fresh.)