The stunned look on Scarlett Johansson’s face during a “vulgar” joke swap segment on “Saturday Night Live” in December was no act.

For the pair’s joke swap skit, Jost, 42, was forced to read Che’s absurd quips about Johansson — including one where Jost said he’s “eating roast beef every night since my wife had the kid” — as the actress watched from backstage in shock.