Killmer was born in Crowley, Texas. She attended Baylor University, graduating in 2010 with a performing arts degree. Killmer appeared in the Hulu reality television web series If I Can Dream in 2010, which featured a number of participants who were trying to make it in the entertainment business. In 2014, Killmer was cast in the NBC pilot Tin Man,but it was not picked up by the network when it announced its 2014–15 television schedule.In 2014, Killmer joined the cast of the NBC drama Chicago Fire as Sylvie Brett, the paramedic who replaces Leslie Shay (Lauren German) in the third season premiere,"Always", which aired on September 23, 2014. She starred in Beyond the Mask, a Revolutionary War action thriller released on April 6, 2015.