在这部结婚已七年喜剧/爱情片中,Jennifer（Natalie Hall）和Kevin（Darin Brooks）从六岁开始就是「死党」了，但两人的人生之路却完全不同。Jennifer从大学毕业后投身慈善事业，还买了一套新公寓，而Kevin大学没读完就辍学了，至今居无定所。作为对朋友的帮助，Jennifer打算让Kevin搬到自己家里来住——直到他重新振作起来。
七年之后，Jennifer的事业顺风顺水，而Kevin仍然一事无成。Jennifer不介意Kevin按照他的想法来生活，但是她的新男友、傲慢自大的公司高管Bryce（Ryan Doom）介意，Bryce一再要求Jennifer将Kevin赶出去。Bryce用花言巧语博得Jennifer的欢心，在和她约会六个月后就向她求婚，Jennifer欣喜若狂。实际上Bryce打算利用Jennifer在慈善界的名声来讨好自己的老板Von Hoffman（Frances Fisher）。
Kevin发现Bryce对Jennifer不忠，决心要帮助Jennifer脱离苦海。在读法学院的兄弟及好心肠的邻居Henderson先生（George Wendt）的帮助下，Kevin发现一个惊人的事实：根据普通法的规定，只要男女双方同居七年就可认定为「事实婚姻」。现在Kevin打算和Jennifer在一起过一辈子，但Jennifer和他有同样的想法吗？
Jennifer and Kevin have been inseparable since becoming best friends at age six. So when Jennifer graduates from college and begins building a career in charity, she thinks it's only right to let drop-out Kevin live in her newly purchased house until he gets back on his feet. Seven years later, Jennifer is continuing up the career ladder while Kevin is still golf caddying and waiting for his big break. Jennifer is happy to let Kevin march to his own beat, but her new boyfriend, arrogant corporate manipulator Bryce, wants her to kick Kevin to the curb. Oblivious to his cheating ways, Jennifer is ecstatic when Bryce asks her to marry him after only six months of dating, secretly using her angelic reputation to gain favor with his boss Mrs. Von Hoffman. Kevin catches Bryce cheating and is determined to spare Jennifer an unhappily ever after experience. With a little help from his brother who is in law school, and support from his meddling neighbor Mr. Henderson, Kevin finds out he is legally married to Jennifer in a common law marriage after living together for exactly seven years. Now it's up to Kevin to prove he is Jennifer's equal, forever.
