Siren (Forbidden Siren) Secrets and Unlockables (PS2)

Siren or Forbidden Siren in Europe and Australia, is a stealth-based survival horror video game developed and published by Sony Computer Entertainment for the PlayStation 2 console in 2003. The game tells the story of several characters (most of whom are playable) trapped in an old Japanese village over the course of three days. Siren is set in a remote, rural Japanese mountain village named Hanuda, which is characterized as being very traditional and particularly xenophobic. Following a ritual ceremony, the village teeters wildly between time and space, with an infinite sea of red water in place of the usual surrounding mountains.

The story focuses on the efforts of Hisako Yao, the leader of a strange local religion, to resurrect or re-awaken an extraterrestrial being known as Datatsushi through an occult ceremony. While Datatsushi is indisputably alien, the methods used to resurrect it and the effects of its presence seem to be supernatural in nature. The siren of the title is the call of Datatsushi, summoning the residents of Hanuda to immerse themselves in the red water, thus creating an army of subordinates called shibito.

Unlockables

Puzzle Game (PAL) - Acquire archive 087 on Kyoya Sudo's stage, Day 3, 03:00

Stage Select - Complete the first 19 missions in the game.

Time Attack Mode (PAL) - Complete every scenario and objectives one and two for all stages.

Secrets

Archives Trick
After you finished the game and unlocked the zuno game, go to the stage where your archive is missing, take it, then in the menu select Back To Title. Then, enter the zuno game and immediately exit. The game should ask you to save your game file. Save and the archive will be saved too.

Hidden Movie
Complete the game without the second ending and collect all 99 archive items to unlock the 100th item. Go to the Stage Select screen then move the cursor to the upper right corner, and start the movie.

Here's one of the game's ending cutscenes: