Becki Newton, Neil Patrick Harris

Beginning February 13, former Ugly Betty star Becki Newton will bring her sexy sass to How I Met Your Mother — and shove it in Barney's face (for the rest of this season and likely into the next). "My character will present a real challenge to Neil Patrick Harris and give him a run for his money," teases Becki of her character, Quinn. "She kind of has Barney figured out before he even starts talking."

In other words, are we to assume Quinn is as promiscuous as Barney? "Perhaps, yes," she says. "And it's so much fun! For Barney, it will be like looking in the mirror. He's not used to someone speaking his language, and it's going to rock his world."

Turns out Becki cast herself in the role after meeting with the show's producers. "She sat down and said, 'Barney needs a love interest and I should be that girl,'" reveals exec producer Craig Thomas. "She wanted to come on as a formidable force to complicate his world." Complications involve several secrets that Quinn is keeping. "The final 30 seconds of her first episode, in a scene without any of our cast, will reveal who she really is. She's basically a puppet master playing Barney." Expect Ted to drop a Quinn-related bomb on love-struck Barney a few episodes later.

While Becki's meshing with her new TV family, she hasn't forgotten her Betty roots. She and her son recently got together with Ana Ortiz, Ashley Jensen and their babies. Says Becki, "We all know each other so well that it felt oddly normal to have our little ones with us."

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