The movie opens with a voiceover by Jane (Katherine Heigl) as she explains when she first discovered her "calling" in life. The scene is from her childhood when she, her younger sister Tess and their father attend a realtive's wedding. This is shortly following the death of their mother so Jane must act as a mother figure for her sister. When her father asks Jane to take Tess to the bathroom, she comes across a distraught bride who has torn a seam on her dress leaving a whole at the back of the bodice that shows the upper half of her rear end. Jane has a moment of epiphany and uses her sister's hair ribbon and sews up the back fo the dress in a becoming way. The ecstatic bride then asks Jane to carry her train down the aisle as a reward.Flash forward in time to the present -- Jane is in a bridal shop with seamstresses all around her hemming a wedding dress. A woman walks in and says "The bride is on the phone" where you discover that Jane is the same size as the bride and is doing her bridesmaid duty of having the wedding dress hemmed the morning of the wedding for the panicking bride. She leaves the store, dress in hand, wearing her bridesmaid dress and hurries to the nuptials making it in time for the bride to change and get ready for her ceremony.
During the ceremony,
