The ASP was a custom take of the S&W Model 39 autoloading pistol developed by a man named Paris Theodore in the 1970s. Theodore made a wide variety of sneaky James-Bond-like guns for various clients, but is best know for the ASP. At the time, it was one of the best options for a subcompact pistol in a full-power pistol cartridge (9×19). In addition to cutting down the slide and grip and dehorning the whole gun, the sights were replaced with Theodore’s proprietary “guttersnipe” sights to provide a very fast (and “accurate enough”) sight picture for close quarters shooting.
When Theodore sold his business in the late 70s, it was purchased by folks who continued to make the ASP pistols in Wisconsin, where this particular one came from.