Scott Free was the chosen legal name of the DC Comics character who went by the costumed name Mr. Miracle. His specialty was being an escape artist of universal caliber, rather like Harry Houdini crossed with James Bond (so that he'd have adventures worth writing about in kids' comic books).
You've probably have never heard of him, unless you're a fan of The Sandman and saw his cameo in the fifth issue of "Preludes and Nocturnes" or spotted him in the third issue of the company-wide Kingdom Come crossover series.