Katie's sister is getting married to a man who is too old, too fat and too geeky. He also happens to be a teacher at Katie's school - how embarrassing! But it gets worse. Katie has been asked to be the bridesmaid. Yuk! How will she ever live down the shame of having that man as a brother-in-law, and having to wear a frilly blue dress for a whole day? It's time for action. Katie has to find her sister a new boyfriend, and fast.