"As hard as we all tried, the Prison Break powers that be and I were unable to find a way to meet both the needs of the story and the needs of my family. We parted wishing each other well. I had a wonderful time working with the creative team and have a world of respect for all of them; they took great care of Sara. I'm also enormously grateful to the fans. They've been so gracious and supportive, and I hope thehy continue to enjoy the show."
Callies at the Edmonton Expo 2013
However, in March 2008, Olmstead stated that the character of Sara is still alive and would return in Season 4 of Prison Break. Though the character Sara Tancredi appeared to have a violent death, Olmstead stated "...we realized that there was actually a way she could still be alive." When asked by Kirstin of E! whether the fans' overwhelming response to her death had factored in, Executive Producer Matt Olmstead admitted it had indeed influenced the decision.
In 2010, Callies was cast in her biggest role to date, main character Lori Grimes on the AMC horror/drama series The Walking Dead, based on the comic book series of the same name, from the show's start until season three. Grimes, her family, and friends are forced to fight relentless evil in the form of flesh-eating zombies and the few surviving humans, some of whom are even more diabolical and dangerous than the zombies themselves. Callies convinced the show's writers to kill her character because that is what had occurred in the comic book version. The drama is by far the highest rated in cable television history, and the first three seasons have received good reviews from professional critics, whether "universal acclaim" or "generally favorable".
Callies has also starred in two feature films - Universal Pictures' Whisper and an independent film, The Celestine Prophecy. In April 2010, she appeared on the Fox Television drama House M.D. as a patient of the week, whose open marriage fascinates House and the team. In August 2010, Callies' first screenplay, an adaptation of Campbell Geeslin's children's book Elena's Serenade, was optioned by producer Cameron Lamb and Canadian production company The Film Farm. Callies starred in the Nigerian movie Black Gold (2011) and one of the female lead roles in the Canadian thriller Faces in the Crowd (2011).
On July 21, 2002, Callies married Josh Winterhalt, whom she met at Dartmouth College. Winterhalt is a martial arts teacher. On January 23, 2007, her publicist announced that the couple were expecting their first child. In July 2007, Callies gave birth to a girl, Keala Winterhalt.
She was voted one of Maxim's "The Hottest Women of Fall TV '08."