Katy Perry swaps mascara for mud in her 'Part Of Me' video.

You know what they say: when the goin' get tough, the tough cuts off her hair, ACE bandages her chest, trades in her cellie for combat boots and enlists in the Marine Corps! Well, they don't say that, but Katy Perry's "Part Of Me" video may make the girlfriend-to-girl-power makeover a common video trope.

So, the main plot point of Katy Perry's "Part Of Me" video, directed by Ben Mor, is pretty singular and straightforward: Katy gets cheated on (not understandable), flips out (understandable!), butchers her hair (in the liberating/ new-beginnings way, not in the Samson way), enlists in the Marines, (dramatic, but... okay!) and kicks ass as a recruit, all the while looking, as we pointed out in our "Part Of Me" video preview, flawless in face paint.

Although Katy Perry has specifically stated that she wrote "Part Of Me" years ago and that the song (which made chart history when it debuted at #1 in February) is not a response to the news that she and Russell Brand filed for divorce, what better panacea for a bad relationship than getting your aggression out via bear crawls and hand-to-hand combat? Also, she excels at that horrifying looking rope-climbing obstacle, the thought of which is enough to make me cry in a heap on the floor and yet still never exercise.

Watch Katy Perry's "Part Of Me" video after the jump.

"Part Of Me," from Katy Perry's upcoming Teenage Dream: Complete Confection album, involves lots of pretty water imagery (cleansing!), a volume of patriotic symbolism usually reserved for Kid Rock videos (Party in the USA!), and possible metaphorical references to "Love Is A Battlefield," (but that may just be me because I see Pat Benatar in almost everything).

"Part Of Me" was filmed at an Camp Pendleton in Oceanside, California, and Katy's fellow troops in the video are actual Marines. It's an unexpected move from the girl we're used to seeing in stilettos, electric hair in a candy land of her own design. "Part Of Me" is the newest recruit in the breakup-ballad battalion (alongside Corporal Clarkson's "Since U Been Gone"), and Katy uses the video to prove that Private Perry needs no saving -- she can save herself just fine -- and that she's just as capable of going G.I. Jane and shooting assault rifles as she is shooting whipped cream out of her boobs.

+ Watch Katy Perry's "Part Of Me" video, and watch "MTV First: Katy Perry," for a revealing one-on-one interview.