Bob is really in over his head, now! He's surrounded by more mooks than he could hope to defeat on his own. Suddenly, a stranger in full armor comes from nowhere and makes quick work of the whole lot of baddies. The warrior then turns to Bob, takes off his helmet and... holy crap! It's a girl! Alice arrives!
Samus Is A Girl is when an Action Girl is well established as heroic, or otherwise badass [...] [tvtropes.org]