Poor ol' Prototype. You'd think June would be a good month to launch a solid piece of new IP and, with Activision's backing, see it take the top spot.
Thing is, The Sims 3 was released this month, and retains its #1 position ahead of the hoodie-clawing simulator. Something it'll probably do for a few weeks to come, because when you see a PC game atop the charts in Britain, you know it's selling well.