Favourite Video Game Plot?

[Froge]

Since I treat video games much as an art form, I do play a lot of games for their story. In fact, I find that video games can be even more immersive than films or books when it comes to telling a story, since you have direct control over the characters.

Spoiler below!

One of the reasons why I like Frictional Games so much is because their games, especially the Penumbra series, are very plot heavy that raise a lot of interesting philosophical questions and inquiries. I noticed that Amnesia had an "obedience to authority" theme going on, as Daniel's unquestioning following of Alexander's orders can be quite easily paralleled to Philip's statement in Requiem that returning to humanity (boat ending) is no different than joining the Tuurngait hivemind. Clearly the makers of this game know and have read about Milgram's experiments.

Anyways what's your favourite video game plot?