So Regina George (who we last saw in Mean Girls) is all getting in C-Tates (who we last saw in Step Up 2: The Streets) business, and they love each other. Then they park their car and start making out. Big mistake. They get rear ended, and the truck decides it's not going to stop until it plows them into a telephone pole. Regina George goes through the windshield, which is a major bummer, because she was already hit by a bus in Mean Girls. This girl should avoid traffic at all costs. I cannot stress enough that you should never park the car and start making out. Road head is a much safer option.
Anyway, she wakes up in the hospital, but she not only forgets what a great dancer C-Tates is, she forgets him altogether. In fact, C-Tates forgets what a great dancer he is, but he remembers something about music, and he has a studio. Unfortunately, he uses it for making music instead of grooving to music. I assumed the love story would revolve around C-Tates love to pop and/or lock it, but they never touch on that. This was obviously disappointing to someone who loves to dance.
Then her parents come back, but they are evil. We know this because C-Tates frowns at them, but they are being super nice and want to help their daughter. Note: Her Mom no longer has boom implants and does not look like Leslie Knope anymore. She may be an impostor, but the documentary doesn't go over that part.
Some dude with bad teeth used to be engaged to Regina. C-Tates says he knows all about him, which is a way at hinting that he has a tiny penis/prematurely ejaculates with the softest touch from a woman. This was never said, but I sat laughing during this scene, because me and C-Tates never forget when ladies tell us how manly we are compared to past lovers.
Turns out her best friend (Gretchen Weiners) had sex with her Dad. She gets super pissed at her Mom for lying to her. Then her Dad feels bad that she is not turning out the way he had envisioned, as a world class Lacrosse player/lawyer, but she is going to be an artist instead. Regina consoles him, which is weird, because she was mad at her Mom just a few seconds earlier, but she still likes her Dad. I think she realizes that her best friend is pretty hot, and Mom was not giving into her Daddy's sexual desires, so pops really had no choice.
This makes her remember that it is time to give up her lady parts to her man-piece, and hopefully that will bring back C-Tates's desire to dance, because Magic Mike will be impossible if he stays in the music industry.
So that is everything that happened in The Vow. You're welcome.