Robert De Niro, Ben Stiller make cameos on 'SNL' as Robert Mueller and Michael Cohen

In this Feb. 4, 2016 file photo, Ben Stiller poses for photographers upon arrival at the premiere of the film "Zoolander No.2," in London.PlayAP
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Hollywood A-listers Robert De Niro and Ben Stiller made cameos on the cold open of "Saturday Night Live" this week as they took on the chaos surrounding the Robert Mueller investigation.

The episode opened with Kate McKinnon's Jeff Sessions and Beck Bennett's Mike Pence worrying about the raid on Donald Trump's lawyer Michael Cohen's office.

They welcomed Cohen, played by Stiller, to their office.

"Michael Cohen, attorney at law -- and also sometimes not at law," he introduced himself.

As the real Trump complained on Twitter last week as word of the raid on Cohen broke, Stiller worried about the investigation destroying attorney-client privilege -- or, as he called it, "attorney-criminal" privilege.

"This whole thing is a violation of attorney-criminal privilege. ... I'm Donald Trump's lawyer, I've got a whole hard drive that's just labeled 'yikes,'" Stiller said.

De Niro would then give Stiller's Cohen a lie detector test, which he failed when asked if Trump knew about the payment of $130,000 to Stormy Daniels.

The show even got a chance to make a callout to De Niro and Stiller's famous "Can you milk me?" scene in the duo's 2000 comedy "Meet the Parents."

"I just tried to milk some information out of people," Stiller said. "So what?"

"Did you say 'milk?'"

"Yeah, like with a cow, or a goat ... or a cat," Stiller responded. "You can milk anything with nipples."

"Really? I have nipples, can you milk me, Mr. Cohen?"