Real estate agent Peter Klaven (Rudd) seems to have it all in life. That is until he gets engaged to girlfriend Zooey Rice (Jones) and realises that he's been too busy with his relationships and career to make any real friends.
Desperate to find a best man for the wedding, Peter embarks on a number of disastrous 'man dates', his luck finally changing when he meets laid-back Sydney Fife (Segel).
Instantly bonding over their love of Canadian rock act Rush, the two become inseparable, but while Zooey is initially pleased that Peter's finally found a best buddy, soon their hetero love affair begins to take its toll on the upcoming marriage.
While it may be a thin concept, the endearing cast and a generous helping of close-to-the-bone gags keeps things moving along nicely. Playing out like a non-threatening version of Fight Club with Forgetting Sarah Marshall star Segel in the Tyler Durden role, Hamburg's film manages to be rude, crude and charming, mostly due to the easy charisma of the two leads.
The unsung hero of comedies such as Anchorman and Knocked Up, Rudd continues his smooth transition from fine supporting player to likeable lead, although Segel isn't really given enough to get his teeth into, despite getting the opportunity to pick a fight with Lou Ferrigno, aka TV's Incredible Hulk.
Neatly nipping any accusations of homophobia in the bud by casting Andy 'Hot Rod' Samberg as Peter's non-stereotypical gay brother and JK Simmons as their hilariously blunt gay-friendly dad, I Love You, Man may not be original but it's a good-natured dollop of fun.