Wendy lived in McKinley, Pennsylvania, with her younger sister Julie, and her parents, Mr. and Mrs. Christensen. She attended McKinley High School and was the school's yearbook photographer. She was also dating Jason Wise and was the best friend of Carrie Dreyer, she also had Kevin Fischer in her group, who was her best friend's boyfriend. Wendy and Julie were known for not getting along, as they had distinct personalities. She apparently wasn't very close to other peers outside of her group, with the apparent exception of the popular girls Ashley Freund and Ashlyn Halperin, who Wendy seemed to be friends with
Wendy Christensen visited the carnival with her boyfriend Jason Wise, best friend Carrie Dreyer, and Carrie's boyfriend Kevin Fischer for their senior class field trip. When they board the Devil's Flight roller coaster Wendy has a premonition that the roller coaster will crash, killing everyone on board. When she panics a fight breaks out between Kevin, and fellow students Lewis Romero and Ian McKinley. As a result, several students are forced off the ride moments before the roller coaster crashes as Wendy predicted. The remaining passengers are killed, including Jason and Carrie, which leaves Wendy devastated
Weeks later, Wendy, still distraught over Jason's death returns to McKinley High School one last time to pick up her diploma, having decided not to attend graduation. Before leaving she bumps into Kevin who tells her about Flight 180, but Wendy refuses to listen to him and drives off. When she returns home, she looks at the photos she took the night of the accident and realizes that a photo she took of Jason foreshadowed his death. She tries to call Ashley Freund & Ashlyn Halperin to warn them both but is too late as the girls get stuck inside their tanning beds and burn to death
