Alongside the announcement of Steam pre-sales for XCOM: Enemy Unknown, 2K has released a gameplay walkthrough narrated by lead designer Jake Solomon. Things don't start out looking very good for humanity ... until Sid Meier's psionic powers turn the table, that is.

In addition to the new video, we also have the first screens of Enemy Unknown's PC version. Apart from the obvious point-and-click differences, the PC version also features a traditional grid system, which should be familiar to fans of the series.