- Father was a Mormon missionary in France, where he met and converted Mireille's mother.
- Won an Irene Ryan Acting Scholarship while attending Brigham Young University.
- Performed with the New York acting troupe Handcart Ensemble.
- Played identical twins Kathy and Jodean Marquart on the HBO drama Big Love.
- Was five months pregnant while shooting the pilot for AMC crime drama The Killing.
- Prepped for her detective role in The Killing by grilling the series' still photographer, who had spent 20 years as a homicide investigator.
- Holds a black belt in tae kwon do.