Believe it or not, the original BioShock turned 15 this past weekend! Irrational's seminal shooter continues to be one of the very best story-driven FPS titles ever made, and one we still think about often, even 15 years on.

However, we've also been reminiscing about the series as a whole, including the hugely-underrated BioShock 2 (along with its brilliant expansion), and the more divisive but equally entertaining BioShock Infinite.

The underwater city of Rapture is such an iconic setting in gaming, and honestly, it always felt like the series was going to struggle to move away from that location. Still, Infinite's Columbia is a fascinating place to explore, even if the game's focus on all-out action detracted a little bit from the satisfying gameplay loop established in the first two games.

With that in mind, which is your favourite BioShock game? Is it the original with the introduction of its unique location and its shockingly surprising plot twist? Is it BioShock 2 with it's more refined combat mechanics and the ability to utilise the 'Big Daddy' suit? Or finally, is it BioShock Infinite, where the series headed for the clouds in an alternate take on 1900's America?

Vote in the poll, and let us know why in the comments!

Which Is Your Favourite BioShock?