A terror is stalking the land: people are disappearing daily, their bodies appearing covered in savage gashes coupled with precise surgical cuts. The legend of the 'Werewolf of Allariz' spreads across the land like wildfire. When Barbara (Elsa Pataky) falls in love with travelling vendor Manuel Romasanta, she is at first besotted with him - but soon begins to be suspicious of him. What has happened to her sister, who - after being escorted by Romasanta to the city - seems to have disappeared forever.
| Actor | Role |
|---|---|
 Julian SandsManuel Romasanta | Manuel Romasanta |
 Elsa PatakyBárbara | Bárbara |
 John SharianAntonio | Antonio |
 Gary PiquerDistrict Attorney Luciano de la Bastida | District Attorney Luciano de la Bastida |
 David GantProfessor Philips | Professor Philips |
 Maru ValdivielsoMaría | María |
 Luna McGillTeresa | Teresa |
 Carlos Reig-PlazaGómez (as Carlos Reig) | Gómez (as Carlos Reig) |
 Reg WilsonJudge | Judge |
 Ivana BaqueroAna | Ana |
| LLaura MañáAntonia | Antonia |
| SSergi RuizFrancisco | Francisco |
| IItziar FenollarBenita | Benita |
| CCarlos SanteHunter 1 | Hunter 1 |
| JJaume MontanéRaúl | Raúl |
 Arantxa PeñaHelena | Helena |
| AAnna EstellésPaula | Paula |
 Ben TempleDefending Counsel | Defending Counsel |
 Tacho GonzálezPolice Officer 1 (as Taxo González) | Police Officer 1 (as Taxo González) |
| PPep GarcíaLaborer | Laborer |
| AAlejandra JunoLaundress | Laundress |
 Jesús BerenguerMerchant | Merchant |
| JJohn EasthmanPolice Officer 2 | Police Officer 2 |
 Macarena GómezRomasanta's Victim (uncredited) | Romasanta's Victim (uncredited) |