Strange reports are coming in from across Beverly Hills—ordinary gym-goers are suddenly transforming into hulking, super-muscular giants with uncontrollable strength and even worse tempers. When gym equipment starts collapsing, streets crack under heavy footsteps, and panicked fitness instructors call for help, WOOHP sends Sam, Clover, and Alex to uncover the source of the bizarre buff-outs. What starts as a routine investigation quickly points to a suspicious new bodybuilding supplement sweeping local gyms. Determined to track its origins, the girls go undercover among fitness fanatics, testing odd samples, dodging aggressive bulked-up brutes, and following clues that lead them straight into the plans of a villain bent on creating a super-strong army. As the transformations spread faster than expected, the spies must race against the clock, relying on their gadgets, their smarts, and their ability to keep calm under pressure—before Beverly Hills is overrun by unstoppable, muscle-bound monsters.

As the spies dig deeper into the mystery, Alex volunteers to check out the most chaotic gym—the one where three trainers reportedly burst through a wall mid–yoga class. Ever the energetic optimist, she arrives disguised as a new trainee, ready to blend in. But the moment she steps inside, she realizes she may be in way over her head. Massive, over-pumped gym members stomp across the floor, lifting weights so heavy the metal groans. One accidentally tosses a dumbbell across the room like a frisbee, and Alex barely dodges it, tumbling into a stack of yoga balls. Trying not to draw attention, she jokes, “Wow, intense warm-up, huh?”—but no one is laughing. Using a discreet WOOHP scanner hidden in her sweatband, Alex analyzes the empty supplement bottles scattered around. The readings spike with strange biochemical enhancers—way beyond anything legal. When she slips one bottle into her bag, a towering, bulked-up athlete spots her and growls, “Hey… that’s my protein!” Alex tries her signature friendly smile, hoping to charm her way out of trouble. It works for half a second—until the guy flexes so hard the floor tiles crack. With no time to waste, she somersaults between weight racks, darts up onto a treadmill, and blasts away as the machine speeds to max. She vaults over the railing, flips through the air, and lands near the exit just as Clover and Sam burst in to help. Out of breath but triumphant, Alex waves the bottle. “Good news! I found our clue! Bad news… we should really run!” Behind them, half the gym begins to bulk up even more, ready to charge. The spies sprint out together, knowing Alex’s discovery might be the key to stopping the entire muscle-growing epidemic—if they can escape the stampede first.

In the end of the missions, supervillain Ulrich Wernerstein created Bulky Bars, which are chocolate energy bars that make whoever eats them become stronger but more primitive. In a moment, Alex decides to eat the bars to become stronger and be able to defeat him.

Alex: (unwrapping bar after bar) Okay, I know Sam said these were dangerous but… I’m STARVING. One more won’t hurt. …Or two. …Or— (laughs nervously) —okay, maybe six. Clover: Alex, STOP. That’s not a snack pile, that’s a biochemical disaster waiting to happen! Sam: Put the bars down. Slowly. Carefully. Preferably before swallowing them. Alex: (already munching loudly) Too late! Mmmph! These are so good. Why does evil food taste amazing? Clover: Sam… her pupils are doing something weird. Sam: Alex, how many did you eat? Alex: Uhhh… (tries counting her empty wrappers, gets confused) A… bunch? Like… all of them? Hehe… numbers are hard right now. Clover: Oh no. Oh no no no— (A low rumble starts. Alex’s muscles twitch. Then explode outward in comically rapid bulges.) Alex: WHOA! My arms feel like… like balloons! But, like… muscle balloons! (flexes uncontrollably) Hehehe look, guys! I’m JACKED! Sam: This is very bad. The serum’s hitting her system all at once! Alex: (voice deepens slightly) RAAAH! I feel AMAZING! (lifts a vending machine over her head)