A good-natured womanizer and a serial cheater form a platonic relationship that helps reform them in ways, while a mutual attraction sets in.
Regan (Kirsten Dunst) is used to being first at everything. Imagine her horror and chagrin when she finds out the girl everyone called Pig Face (Rebel Wilson) in high school is going to tie the knot before she does! But Regan sucks it up and takes on bridesmaid duties along with her childhood pals: substance-abusing, promiscuous Gena (Lizzy Caplan) and ditzy Katie (Isla Fisher). The single ladies are determined to put their bitterness aside and have an awesomely hedonistic bachelorette party.