Two long-lost identical twin sisters meet at summer camp and decide to try to get their parents to reconcile by switching places.

I’m breaking down movies by their three-act structure. What is three-act structure? I explain it here.

Note: I break the story down into five-minute blocks to make it easier to see the length of each section. Rough time codes follow.

Prolog

Girls arrive at Camp Inch (introducing the setting). 5

Act 1

Susan & Sharon meet in the dining hall (introducing the heroes with the inciting incident). Later, on the lake, Sharon responds to Susan’s jibe with a prank. Susan and friends retaliate with a bigger prank that gets Sharon and friends barred from the dance with the boys’ camp. 10

Sharon gets back at Susan at the dance. Susan and Sharon fight and cause a disaster. 15

As punishment, they must share a cabin. The girls warm to each other. 20

They find they have the same birthday. Susan brushes it off, but when Sharon shows Susan a picture of her mother (which Susan recognizes from a picture her father used to keep), they realize they must be twins whose parents divorced (the call to adventure). They console each other (the refusal of the call, sort of). 25

The girls scheme to switch places so they can each meet the other parent (the motivation to act). This will force their parents to visit in order to switch them back–an opportunity for them to reconcile. They practice acting like each other. 30

Act 2

Susan is warmly welcomed in Sharon’s home in Boston (entering the extraordinary world of impostorhood). 35

Susan gets Maggie to tell her about her relationship with Mitch. 40

Sharon is warmly welcomed in Susan’s home in California (entering the extraordinary world of impostorhood). 45

Sharon sees Vickie & questions Verbena (plot twist 1). She takes a disliking to Vickie. 50

Sharon & Susan have a call & argue over rushing the scheme. 55

Susan tries & fails to get Mitch to talk about Maggie. She opens up to Verbena. 60

Mitch tells Sharon he’s marrying Vickie (an obvious crisis). She reacts badly. 65

Midpoint

Susan opens up to grandpa. He makes her come clean to Maggie. 70

Grandpa gets Maggie to update her look before going to California. 75

Maggie and Susan come to California (rallying the girls’ morale). Vickie & friends arrive to discuss the wedding. 80

Mitch is dumbfounded by Maggie. The girls reveal themselves. 85

Mitch & Maggie argue. She punches him (plot twist 2, and a terrible choice). 90

Maggie is introduced to Vickie. 95

The girls recreate Mitch & Maggie’s first date. 100

Mitch & Maggie argue. Maggie intends to take Sharon home (a devastating defeat for the girls and a ticking clock). 105

Act 3

The girls dress alike and refuse to reveal their identities (the secret key) so they can insist they all go camping together (turning the tables). But Vickie goes instead of Maggie. 110

The girls make camping miserable for Vickie. 115

The girls prank Vickie, & she slaps one. Mitch protests, and she leaves. Back home, the girls apologize to Mitch and, more or less, give up (a final setback of sorts). 120

Maggie cooks for Mitch (the climax). They confess their feelings (resolving the central conflict). 125

Epilog

The girls awaken in the morning, and one relates her dream of their parents getting remarried (the presumed decision about the future). 130