Russell Brand shamelessly hits on married 'Smash' star Katharine McPhee on Fallon [Video]

Dave Nemetz
Yahoo! TV

You might know that former "American Idol" finalist and current "Smash" star Katharine McPhee is happily married. But apparently, Russell Brand didn't know that, judging by the way he aggressively flirted with McPhee when the two shared the couch last night on "Late Night With Jimmy Fallon."

Or shared a chair, we should say, because when McPhee came out, the British comedian immediately invited the young actress to sit on his lap, calling her "beautiful" in the process. Poor Kat tried to tell Jimmy a story about her trip to the Super Bowl and exchanging numbers with the 49ers coaching staff, but Brand couldn't help inserting himself into the conversation: "As you know, I've announced it: I find Katharine very attractive. And when she said 'exchange numbers,' I thought of things I'd like to exchange with her." In case we missed the joke, Brand later added, "Genes. Genetic info... data." (There's a fine line between charmingly bawdy and just plain gross, and Brand may have crossed it here.)

[Related: Why We're Giving 'Smash' a Second Chance (and You Should, Too)]

McPhee tried to cool him off by making a pointed reference to her "husband," producer Nick Cokas. But did that stop Russell? Of course not! Referencing her earlier slam of the New York Jets, he joked, "Look at the way you dropped the Jets; you could drop that guy any day!" Then he threw in a Bowie quote: "Turn to face the change... ch-ch-ch-changes!" He did add a bit of sober advice, though: "You must never destroy a marriage... unless you're really bored." (Hmmm... how does his ex-wife Katy Perry feel about that little pearl of wisdom, we wonder?)

Brand did eventually get the hint, though, interrupting once again to say, "I didn't know you were married. I'm gonna f--- off now," before exiting the stage while shouting to the audience, "I didn't know! Be clear!" That's a lesson to all you ladies out there: When meeting Russell Brand, announce your marital status loudly and clearly so this sort of awkward incident never happens again.