#.38 special 

In a world of snow and ice in the Great White North, there was a little girl born and raised with blades on her feet.  She longed, however, for an escape from the bitter cold, and, at the very first chance she got, she fled to the land of longhorns and mustangs. 

She landed in a place that is warmer, although even more  deadly - Texas - and assumed her current (and very appropriate) nom de doom; Sloane Gunman.

Trading in her blades for wheels, she is a mild mannered teacher by day, and feared roller derby assassin by night.   With a killer stride and even deadlier hits, you never know she's behind you until you hear  the sound of her wheels - and then it's too late!