Little is known of the life of Byrna Brilyant prior to her first encounter with Wonder Woman in 1946.  At that time, she was a school teacher in Fairweather Valley, an idyllic Southern dale that historically retained a temperate climate.  Her father had moved there to conduct experiments creating "blue snow", which he believed would benefit humanity.  When he died, his greedy daughter inherited his notes, equipment and access to blue snow.

In the fall of 1946, Fairweather Valley begin to freeze over, attracting the attention of Wonder Woman.  As she flew there with Steve Trevor and Etta Candy, her plan began to freeze causing them to abort the flight.  Inspecting their damaged craft, the found it covered in a blue snow.  On a nearby farm, Wonder Woman witnesses frozen cattle and learns of a farm wive's frozen daughter, victims of a "Blue Snowman" who was demanding ransom to thaw their relatives and property.

Entering the town, Wonder Woman found the mayor and other leaders squabbling, frustrating local school teacher Byrne Brilyant who was acting as their secretary.  Wonder Woman convinces them to "pay" the ransom, allowing her to see who came to collect.  A robot in the form of a Blue Snowman arrives and receiving the ransom, returns to its base.  Wonder Woman lassos it, allowing herself to be carried along to the a lonely mountain top.  There she meets the real Blue Snowman and after losing her lasso to one of the Snowman's robots, is captured by the criminal and dropped into a vat of blue snow. 

As she slowly freezes, Trevor and the Holiday girls race to the rescue.  Distracted by them, the Snowman does not see Wonder Woman reach the bottom of the vat and catapault herself free.  Catching the villain unawares, she forces the Snowman to defrost the valley using her lasso and returns to town.  There she unmasks "him" as Byrna Brilyant, using her father's science for crime.  The snow rays is disassembled and Brilyant is taken to Reform Island (Sensation Comics #59).