Unseen Syndrome is the main theme for the distant future chapter, "Mechanical Heart". It only plays shortly in two spots during the actual chapter: when Rachel almost throws Cube off the ship via space lock while she's going insane over Kirk's death, and then again when you expose the fake Cube towards the end of the chapter. It also plays for the second half of the chapter staff roll.
Unseen Syndrome is an odd song in that it doesn't seem like there is a set loop point for the entire song, but rather each individual channel has a different loop point. It is unknown where the true loop point is in the song at the current time.
This song is track 14 on the official soundtrack, but there are two different variations of the song, both of which are not on the soundtrack and are unofficially named.
The first variation is simply the base-line of the song with a pulsing irregular beat in the background. This is actually the first song to be played in the chapter, and is played when Kirk's life system fails up until you enter the sick bay. It later plays again towards the end when the Behemoth pushes you into a tunnel and corners you until you enter Kato's room.
The second variation is the same as the first variation except without the pulsing in the background. This variation plays when you find Kirk's body is missing until the scene goes to Rachel's room, and the again during the computer message in the guest room after finding the captain dead.
- English: Unseen Syndrome
- Japanese: Ｕｎｓｅｅｎ Ｓｙｎｄｒｏｍｅ