(Los Angeles) - The actress who portrayed Lois Lane in the original 'Superman' movies has passed away, according to TMZ.
Margot Kidder passed away Sunday in Montana but her cause of death is unknown. Kidder co-starred with the late Christopher Reeve in the 1978 film and its' three sequels.
She also had a stint on Broadway and guest roles on T-V shows 'Smallville' and 'Brothers and Sisters'. Kidder was public about her struggle with bipolar disorder, and served as an advocate for mental health.
(Photo courtesy of Getty Images)