In a secondary school, a group of students (Maria, Sonia, Paula, Pol and Esteban) form a tight-knit bunch. Axia, a girl obsessed with supernatural issues, leaving them mesmerized and included in the group. For the 50th anniversary of the center, start some work on improving the facilities. Laura, the tutor of the course offers students a work of the institute history. As they investigate they discover that, during the Civil War, there were tunnels collapsed, leaving people buried who were hiding there, including several children. According to information obtained on the Internet, people are buried "appear" killing. Are the "E.S.O. (Hidden supernatural entities "). When they decide to enter the tunnel adventure turns into a nightmare.
| Actor | Role |
|---|---|
 Fernando GuillénNot listed | Not listed |
| FFon HerreraNot listed | Not listed |
| PPaula JiménezNot listed | Not listed |
| CCadhla KennedyNot listed | Not listed |
| CClara LapeiraNot listed | Not listed |
 Mercè LlorensNot listed | Not listed |
 Sergi MateuNot listed | Not listed |
 Rosana PastorNot listed | Not listed |
| OOriol PuigNot listed | Not listed |
 Pere VallNot listed | Not listed |
 Mireia OriolNiña fantasma | Niña fantasma |
| DDavid MaestrePol | Pol |
| NNatàlia PedraPaula | Paula |
| PPatricia RodríguezEli | Eli |
| IIñaki MartínezPedro (fantasma) | Pedro (fantasma) |
| JJorge CarcassonaSacerdote anciano | Sacerdote anciano |
| KKepa AtxaPortero | Portero |
| AAlejandro SantaeufemiaNiño fantasma | Niño fantasma |
| JJosep Maria ParésNiño fantasma 2 | Niño fantasma 2 |
| AAgustí TrullenNiño fantasma 3 | Niño fantasma 3 |
| JJordi PinelaNiño fantasma 4 | Niño fantasma 4 |
| GGlòria CanoNiño fantasma 5 | Niño fantasma 5 |
| PPujol. FrancescNiño fantasma 6 | Niño fantasma 6 |
 Ginebra VallEstudiante | Estudiante |
| PPere VallEntrenador baloncesto | Entrenador baloncesto |