Big Girls Don't Cry

Kati and Steffi have been best friends since childhood, but as they step into adulthood, both their perfect friendship and their personalities get harshly tested by a series of unfortunate events mainly caused by Steffi finding out that her father was unfaithful to her mother and by the two girls getting hit by the consequences of Steffi's delirious revenge plans. When things get out of hand, the two girls are in the middle of a mess that makes Kati question whether or not Steffi is really so precious to her. Where will Steffi's plans of penalizing her father's "evil" lover end up? Will the girls' friendship be saved?