The Soft Weapon

"The Soft Weapon" is a science fiction short story written in 1967 by Larry Niven, set in his Known Space universe. It was the basis of the Star Trek: The Animated Series episode, "The Slaver Weapon". Niven originally pitched a different story idea for the animated episode, which later became his novelette "The Borderland of Sol".

The story introduces the character of Nessus, a Puppeteer who later became one of the main characters of the novel Ringworld. The story is retold, from the point of view of Nessus, in Juggler of Worlds.

The Soft Weapon was first published in If magazine in 1967 and has since been included in the short story collections "Neutron Star" (1968) and "Playgrounds of the Mind" (1991).

Nessus is returning from a diplomatic mission to the Outsiders, having purchased what is apparently a Thrint stasis box, on a passenger ship run by a human couple, Jason and Anne Marie Papandreou.

They stop at Beta Lyrae to sight-see where they unexpectedly discover, by deep-radar, another stasis box. However, the box is a trap by Kzinti pirates. The rogue Kzinti are using a dummy stasis box to lure ships that they detect to be in possession of stasis boxes. The Kzinti capture the crew and open the looted stasis box, which is revealed to be a Tnuctipun stasis box, not Thrintun. Stasis boxes (which are rare) often contain advanced technological products of immense military value. The Kzinti hope to use the contents of the box to develop weapons technology that will allow them to wage wars of conquest.

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