Sanctuary, Praxian Disintegrator

original movie prop weapon

In fourth season opener Tempus, Helen Magnus has just followed Adam Worth back in time to Victorian London, where Worth is determined to use future technology to save his dying daughter Imogene, and Magnus intent on stopping Worth from catastrophically tampering with the timeline. 

Worth appears on the streets of Whitechapel carrying two large and very incongruous black Pelican cases, containing among other equipment, this pistol. Small but powerful, the weapon is highlighted in two running gun battles through the streets of London, firing green energy bolts capable of destroying walls and vaporizing living beings. Also seen in use in subsequent fourth season episode Resistance.

Metal and painted resin derringer-type pistol, which appears to have been made by modifying a lockback pocket knife. The piece is equipped with a bright blue emitter LED activated by depressing the microswitch trigger, although this illumination is not seen onscreen, where the firing effect is all CGI.

From Legends Memorabilia.