|Voiced by:||Tress MacNeille|
Margaret Madsen was an archaeologist based in Gotham City.
Dr. Madsen personally oversaw the excavation and restoration of an Ultrasaurus skeleton. It took her thirty years, but she finally succeeded and her work was put on display at the Gotham Museum. During an interview with Jack Ryder, Mister Freeze broke into the museum. At first, Dr. Madsen thought Freeze wanted to steal the skeleton, but he actually wanted to take away hope. Without hesitation, he turned his ice gun on the skeleton and froze it, causing it to shatter into pieces. Dr. Madsen watched in horror as her thirty years' work disintegrated in a few seconds, and crumpled in despair.