10 Sci-Fi Movies That Forced You To Answer Impossible Questions

3. Could You Steal Another Person's Life? - Source Code

Duncan Jones' Source Code is a (mostly) terrific sci-fi thriller in which Captain Colter Stevens (Jake Gyllenhaal) is sent into a computer simulation to find the bomber of a commuter train.

But it's revealed later in the movie that, in reality, Stevens was almost killed two months prior, and what remains of his body is on life support.

His consciousness is actually being projected into the Source Code - the final eight minutes before the train bombing, as created by a collection of the memories from those killed onboard.

After identifying the bomber and being allowed to re-enter the Source Code one final time, Stevens' life support is terminated by Captain Goodwin (Vera Farmiga), seemingly ending his life.

However, it turns out that Stevens and this entire fabricated "reality" survives on its own, seemingly creating a parallel universe for Stevens to live out his life with love interest Christina (Michelle Monaghan).

That's all well and good until you remember that Stevens has effectively hijacked the body of Christina's friend Sean Fentress, and even if you consider that this reality is ultimately just a "shadow" of real life, Stevens is still embarking on a relationship with Christina under creepy, false pretences.

Granted, it's certainly a more appealing fate than being dead, but could you truly enjoy a happily-ever-after well aware that your relationship is built on a lie and you're living somebody else's life?