Born Kathryn Ann Sackhoff in Portland, OR, she was the youngest of two children born to developer Dennis Sackhoff and his wife Mary, an ESL educator. Sackhoff was active as a student and participated in ballet and competitive swimming until a knee injury forced her to give them up. She also became involved in drama class at a very early age, winning the lead in several high school musical productions. Sackhoff moved to Los Angeles after her graduation from Sunset High School in Beaverton, OR to pursue a career in acting. There, she waited tables until she began landing roles in 1998, with the first being a supporting role in the TV movie "Fifteen and Pregnant" with Kirsten Dunst, and later, the lead in MTV's failed pilot "Locust Valley." Sackhoff worked steadily over the next few years as a guest performer on television shows and in TV features before landing her first role as a series regular on the short-lived Fox Family Channel program "The Fearing Mind" (2000), about a horror and suspense writer whose life begins to intertwine with the plots of his novels.Sackhoff quickly graduated to a minor role in her first theatrical feature, Christine Lahti's May-December romance "My First Mister" (2001), before landing her second series, "The Education of Max Bickford" (CBS, 2001-02), starring as the headstrong daughter of top-billed Richard Dreyfuss. In interviews, Sackhoff commented that she was especially close with the veteran actor, who took her under his wing throughout the show's brief production. Billed as Katee Sachoff, she next co-starred in "Halloween: Resurrection" (2002) as one of six college students who participate in a reality show contest that requires them to spend a night in the childhood home of horror movie icon Michael Myers, who, unbeknownst to them, has again returned to commit mass murder.The following year, producer Ronald D. Moore tapped Sackhoff for his re-imagining of the much-loved science fiction series "Battlestar Galactica" (ABC, 1978-79). The miniseries, which aired on The Sci Fi Channel in 2003, was met with an overwhelming response by viewers, who made it the third highest-rated original program in the network's history. Less positive, however, were fans' reaction to Sackhoff's casting as ace fighter pilot Starbuck, who had been played as a loveable rogue on the original series by Dirk Benedict (who also voiced a negative opinion of the new show to the press). However, the combination of Sackhoff's performance and the show's exceptional writing effectively took her from lovestruck flight instructor who causes the accidental death of her intended, to a hard-bitten soldier who struggles with her past. In subsequent seasons, she found herself a test subject on a "farm" created by the show's robotic villains, the Cylons, to generate human/Cylon hybrids. By the end of the third season, Starbuck attempted to rebuild her life, but found herself unable to shake the experience and that preoccupation appeared to lead to her death. To her now considerable fan base, Starbuck was seen alive again at show's end. For her work, Sackhoff received two Saturn Award nominations.After ascending to stardom with "Galactica," Sackhoff appeared in several genre-related projects designed to target her main audience. She was a cheery nurse who becomes involved with a man (Nathan Fillion) who is experiencing visions of the recently deceased in "White Noise 2: The Light" (2007), an in-name-only sequel to 2005's "White Noise." She also starred in the direct-to-DVD science fiction feature "The Last Sentinel" (2007) as a soldier helping kung fu star Don "The Dragon" Wilson fight robot soldiers in the future. Sackhoff also joined other "Galactica" co-stars to lend their voice to a 2007 episode of the irreverent animation/comedy series "Robot Chicken" (The Cartoon Network, 2005-), and provided a voice for the popular video game "Halo 3."In 2007, Sackhoff had a recurring role on the revamped "Bionic Woman" as Sarah Corvus, who received bionic prosthetics prior to the show's reluctant heroine, Jaime Sommers (Michelle Ryan), and went AWOL from the program after she discovered it was affecting her mental and physical health. Science fiction fans ate up the action-packed face-off between Ryan and Sackhoff, and the actress showed another facet of her acting talent with her performance, which alternated between feral and vulnerable. Unfortunately, the 2007-08 Writers' Guild strike and low ratings put an end to "Bionic Woman." Instead, Sackhoff simply returned to active duty on "Battlestar Galactica," much to the delight of its devoted viewership.As her duties aboard the Galactica wound down in 2009, Sackhoff picked up a recurring role as Dr. Theodora Rowe on "Nip/Tuck" (FX, 2003-2010), in addition to a hilarious cameo as a fantasized version of herself on the hit geek sitcom "The Big Bang Theory" (CBS, 2007-). The following year, she worked opposite Kiefer Sutherland on the eighth season of "24" (Fox, 2001-2010) as Dana Walsh, a CTU data analyst hiding her criminal past. A pair of cop roles - as Det. Frankie Reed on the long-running procedural "CSI: Crime Scene Investigation" (CBS, 2000-15) and as the voice of Det. Sarah Essen in the animated feature "Batman: Year One" (2011) - preceded her landing a regular cast role on the crime-drama "Longmire" (A&E, 2012-14; Netflix, 2015-). The show, based on a popular series of mystery novels by Craig Johnson, starred Robert Taylor as the eponymous Wyoming sheriff who returns to duty shortly after the death of his wife, only to be confronted by a series of bizarre crimes. Sackhoff played Deputy Sheriff Victoria "Vic" Moretti, a newly arrived transplant from Philadelphia's police department. As the cable network's highest-rated debut drama ever, "Longmire" was quickly renewed for a second season, due in no small part to the contributions of Sackhoff.Outside of "Longmire," Sackhoff remained busy, voicing the character of Bo-Katan on episodes of the animated hit "Star Wars: The Clone Wars" (Cartoon Network, 2008-13; Netflix, 2014) and appearing in the confusingly titled, though surprisingly decent, 2013 horror sequel "The Haunting in Connecticut 2: Ghosts of Georgia." Later in the year, she had her biggest movie role to date, playing the tough mercenary Dahl in "Riddick," the third sci-fi film starring Vin Diesel as the title anti-hero.