Seeking thrillers with friends in a "closed circle"

[Seiryuu]

A slightly odd request, I was wondering if there are any good anime/manga thrillers in which friends are placed in a so-called closed circle or similar scenario, where everyone is stuck in a location and something happens that creates an atmostphere of suspicion, fear, anger, etc., turning them on one another.

There's two basic types of closed scenarios. One has an outside force that triggers chaos, such as a message saying that a limited number of the people involved would be granted some great reward or would be allowed to survive; some would readily kill in order to gain the prize or be one of the ones to survive, and others would just as readily kill in fear of being killed. For instance, there was a manga some time ago with some group of "dragon" masters who were locked in rooms and forced to fight each other for control of their dragons, with a person only being allowed out if they obtained a certain number. Another example from American mystery TV had a man lock three best friends in a cellar and promise to let any two out once they kill the third.
The other type has some internal trigger, such as an incident or a concern over resources. One story in Gosick, for example, has a group of people trapped on a ship with no way out, when someone is murdered. No one knows who did the deed, only that someone among them is a killer. Fear and suspicion quickly grow in the closed space, until they all start killing one another in panicked defense.

I'm looking for something like one of those scenario types, with a group of good friends suddenly or inevitably trapped in a location with some trigger to spawn chaos and turn friend against friend. Any examples welcome in anime/manga, regardless of license, age rating, etc., so long as the story is good.

[Revelation]

For manga, I would recommend Doubt. Definitely that thick tension of a closed environment. Also, the Battle Royale manga/movie defines this genre as well. I haven't read Liar Game yet, but I've heard good things about it that may match your description.

For anime, there's the recent Shiki, though I enjoyed the manga a little better. And, the When They Cry series which includes Umineko/Higurashi no naku koro ni, more so with Umineko. Though, I highly recommend the VN source material seeing as the adaptations were sub-par.

I wish I could think of more series like these, I too enjoy this theme.

[MidoriHiME]

Have you read Battle Royale?

[Flower]

The When they Cry series most immediately jumps to mind here ... but be sure to watch s1 and s2 together. Imo just s1 (which has some pretty graphic violence and even torture btw) leaves way to many question marks over your head. With s2 the series becomes a little more "understandable".

[Sackett]

Cage of Eden?

[Seiryuu]

Cage of Eden definitely sounds like it fits. Higurashi is certainly good as well thx, though the playing field is much larger and more open. Umineko always seemed to go a little fast for me, and the characters might as well be strangers the way they meet only once a year to bicker over inheritance.

I assume with Doubt you're talking about the one by Tonogai Yoshiki, correct? From the description it sounds quite promising. I'll have to take a look. Sounds like the characters met in the incident, right? Are there some with a small space like a building or ship, with people who were already close, as in see each other frequently and have an established friendship?

Supernatural aspects are fine, but I'm hoping for something where the major characters themselves are normal people trying to deal with this without some fancy superpowers. A manga series that's been going recently has a group of schoolmates suddenly trapped in a building with no way out, with ghosts and monsters all around them. Worse, they've seen that people can be possessed, or maybe even copied, and a pair that may or may not be the real people recently claimed to have found out that they could only leave when and if there were only two left alive. This, along with the problems of knowing whether a person's real, and various issues of interpersonal love and conflict makes a very chaotic scenario.

Spoiler for title:

The manga's called "Corpse Party: Musume" and is based on a series of games. In the last chapter I read, one character was discovered to have died long ago and just been reanimated by a malicious spirit, and two characters who seem likely possessed or constructed doubles/impersonations went berserk saying that only two could leave.

[SeijiSensei]

In the H-world, there's

Spoiler:

Body Transfer

[Irenicus]

Originally Posted by Seiryuu

A slightly odd request

Since when was any of your requests not odd.

I kid, I kid.

Anyway,

Tonogai Yoshiki has another, newer manga called Judge. It has a similar premise, somewhat. Same atmosphere definitely.

For a shounen take on the genre, JUMP's been running Enigma lately. To be fair its setting is slightly different from your request and more like the situation in Gosick -- these people didn't know each other beforehand -- but the atmosphere is very much a "survival game" with all the associated trust issues and togetherness and all that. Supernatural, though the kids are your average normal muggles (any more details is spoiler).

Likewise, try Aphorism, which is a story about survival against monstrosities in an enclosed school and how people band together (or forced together, as it were) and all that. It is supernatural but the main character and many other students -- not all -- were very much normal until they were quite literally given powers to fight back. Surprisingly high body count so far.