After completing her work on One Tree Hill she booked a guest role on the fifth season of CSI: NY. She was subsequently announced as joining the cast of Law & Order: Special Victims Unit as Assistant District AttorneyKim Greylek, beginning with its tenth season premiere. She was abruptly written out of SVU in the Season 10 episode "Lead", in which ADA Alexandra Cabot returned. However, McManus continued to be credited in the main titles for the rest of the season. It was later confirmed by the producers that McManus would not be returning to the show. Since then, she has had guest roles in prime time shows Castle, CSI: Miami, The Vampire Diaries, Hawaii Five-0, and other films and/or television shows. She also appeared in the music video 'Glad You Came' by The Wanted. In 2012, she starred as Tara on NBC series Awake.
McManus and Mike Daniels married on June 3, 2011. They reside in Los Angeles, California. In late 2013, it was announced via Twitter that the couple was expecting their first child together. The couple welcomed son Gabriel October Daniels on April 3, 2014.