One of the greatest joys with movies and novels is trying to work out what's going to happen next. Will the story run its course, or will there be some shocking reveal; a last minute deus ex machina to interrupt proceedings? It's what spurs us to finish them, and video games are no different in that regard.
There are thousands of games that play out as you'd expect, and that's fine. Worlds are saved, evil villains get thwarted, dastardly schemes don't come to fruition and all that jazz.
For the most part, that's what we enjoy.
But every now and then, a curveball gets thrown in. The hero you've been rooting for turns out to playing for the other team, or once dead heroes rise from the dead. Perhaps your integrity is tested more than it appears to be, or maybe none of it was real in the first place...?
Maybe we should learn to spot that wearing sunglasses indoors is just too damn obvious a trait for a bad guy?
Whatever the logic behind it, or however clever we think we are when it comes to spotting these tells, some still slip by us. They seem obvious now, but here's some that few picked up on at the time.