Peter Klaven, a
Los Angeles real estate agent, proposes to his girlfriend Zooey Rice, and she accepts. He does not have any close male friends to share the news with, only family and female acquaintances. After overhearing her friends' concern over his lack of guy friends, Peter decides he needs to find some to have a
best man for the wedding. Peter turns to his gay younger brother, Robbie, for advice on meeting men. He makes a series of overtures toward various men, including Barry, the persistently hot-headed husband of Zooey's friend Denise. Barry is not fond of Peter, and Peter, after winning a
beer-drinking contest, inadvertently projectile-vomits on Barry. Feeling rejected, Peter gives up on the best man search. At an open house at
Lou Ferrigno's mansion, which he is trying to sell, he meets Sydney Fife, an investor who is attending the show to pick up divorced women and take advantage of the free food. They become friends, bonding over their mutual adoration of the rock band
Rush. Peter introduces Sydney to Zooey at their engagement party, but a nervous Sydney makes an awkward toast which includes veiled encouragement for Zooey to perform
oral sex on Peter. The next night, Peter attends a Rush concert with Sydney, on the condition that he bring Zooey. During the concert, she feels ignored by them. The next day, while shopping for tuxedos, Sydney asks Peter why he is marrying Zooey, and also asks for an $8,000 loan. After some thought, Peter decides to lend Sydney the money, and later asks him to be his best man. Zooey, meanwhile, has become suspicious of Sydney. Peter tells her that he lent Sydney money and asks her if she knows why they are getting married, since he had no answer to Sydney's question (not aware the question was supposed to stay between him and Sydney). Hurt and angry, Zooey leaves. Peter goes to work the next morning, discovering Sydney has used the $8,000 loan to purchase
billboard advertisements promoting Peter's real estate business (with photos of Peter that Sydney took). Still upset over his fight with Zooey, he confronts Sydney and ends their friendship. Peter then patches things up with Zooey, explaining that although he is nervous, he is ready to get married. As they prepare for the wedding, Sydney finds himself alone and desperate to hang out with someone. At work, Peter discovers that Sydney's billboard advertising campaign was successful. He won back the right to the lucrative Ferrigno listing and many others left messages, wanting him to sell their houses. Feeling encouraged, Peter finally stands up to his insufferable colleague, Tevin Downey, who had been badgering Peter for half the selling rights to the Ferrigno property. Peter slaps him, telling him to back off. Peter feels bad about fighting with Sydney but does not re-invite him to the wedding. Instead, he assembles an array of random groomsmen that includes Robbie, their father Oswald, and Ferrigno. Before the wedding, Zooey sees Peter looking forlorn, clearly missing Sydney. She calls and invites Sydney, who is, unbeknownst to them, already en route to the wedding. Just before the vows are to be taken, Sydney makes a dramatic entrance via
Vespa. He reminds Peter and Zooey that he is, in fact, a successful investor and returns the money he borrowed from Peter, announcing the billboards were their wedding present. Peter and Zooey declare their love to each other, Sydney assumes the role of best man, and the wedding continues. At the wedding reception, Peter and Sydney join the hired band in a rendition of the Rush song "
Limelight" and pull Zooey on stage to join them. Sydney attempts to toast the newlyweds and Peter runs to stop him, remembering Sydney's ill-advised toast at the engagement dinner. ==Cast==