This Justin Timberlake Costar Just Revealed He's Very Well Endowed

Patricia Clarkson revealed Thursday night that Timberlake -- her former "Friends With Benefits" costar -- is seriously packing down below.

While appearing on "Watch What Happen Live with Andy Cohen," Clarkson participated in a segment aptly titled, "How Big Was It," where Cohen asked the actress questions about her career. The late-night host asked Clarkson who had the biggest chance of being her "friend with benefits" IRL while filming the 2011 rom-com, in which she played Mila Kunis' mom.

"Hands down Justin Timberlake," Clarkson said, without hesitation. "'Cause if we want to talk about big ... Sorry, Justin. Oh god."

Cohen, who never shies away from a good scoop, just had to keep prying. "Wow really? Is Justin endowed well?" he asked.

"Well, I had the good fortune to get to see him all there because they were shooting a scene where he couldn't put anything on," Clarkson admitted. "He is a gorgeous man."

"He's gifted below the waist," Cohen said. "Oh, yes," she replied.

"We've been doing this show for nine years, that's maybe the best scoop ever!" Cohen said, to which Clarkson replied, "I mean, oh my god, his mother's gonna kill me."

Speaking of big things, Clarkson also revealed during the game that her biggest paycheck was from the "The Maze Runner" franchise.

During Cohen's other iconic segment, "Plead the Fifth," Clarkson was asked about another former costar, Kevin Spacey.

"You worked with Kevin Spacey on 'House of Cards,' how surprised were you about all of the allegations brought against him?" Cohen asked, referring to his sexual harassment scandal. "Because for some reason, I wasn't."

"Not that surprised," Clarkson admitted. "It was a conversation that was happening," Cohen said, to which Clarkson agreed.

Watch the full game below.