From publisher blurb:
Every Berk in Sigil Struggles to keep his savage sid at bay. But now the bars of the cage are breaking down. . . .
Don't go to sleep, cutter-that's where the shadows slink, gnawing at the frail cord of sanity. The dream-touched sods of Sigil are snapping one by one, turning on each other like wildcats in the streets. And as people become animals, animals become monsters, rending friend and foe alike with fang and claw. The lawful factions have enough trouble dealing with a rash of breakouts form the Prison. But when the shackles of society fall away, it's all a body can do to keep the beast within form bursting free?and running wild.
Something Wild is a Planescape adventure for four to six characters of 4th to 7th levels. When Sigil falls prey to disturbing nightmares and outbreaks of violent fury, the heroes must follow bloody trails to the treacherous peaks of Careeri and the savage jungles of the Beastlands. An ancient terror threatens the planes anew, and only the player characters can stop it from feasting on the flesh of the multiverse.
The Planescape Campaign Setting boxed set is required to run this adventure. The Planes of Conflict Campaign Expansion boxed set, the Planescape Monstrous Compedium Appendix, and In the Cage: A Guide to Sigil are recommended as well.