During the Indian Ocean earthquake of December 26, 2004, Petra was at the Khao Lak resort in Thailand with her main photographer and fiancé, Simon Atlee when the tsunami struck where they were staying. Initially, Atlee was presumed missing, but his body was found and identified on March 3, 2005, on the shores of Sumatra (near the epicenter of the earthquake that caused the Tsunami).

Atlee drowned, and Němcová suffered a broken pelvis and serious internal injuries, but she managed to hold onto the top of a palm tree, reportedly for eight hours, until she was rescued by Thai civilians and airlifted to an inland hospital nearby. Petra spent three weeks in a Thai hospital, and then flew home to the Czech Republic, where she spent an additional three weeks in the hospital. Atlee's body was not found until over two months after the tsunami. Petra's first interview after her near-death experience was with Diane Sawyer on ABC's Primetime Live, on March 9, 2005. She has also spoken