Convinced that a series of coincidences hold some secret to life's largest riddles, Albert Markovski (JASON SCHWARTZMAN) seeks the help of a detective agency unlike any other ... which leads him down a path that questions the essence of existence itself.
In an attempt to ferret out the meaning of these flukes, he consults Bernard and Vivian (DUSTIN HOFFMAN, LILY TOMLIN), AKA the Existential Detectives, a pair of married metaphysicians who fearlessly investigate the mysteries at the core of their clients' secret innermost lives. When on a case, these two follow their clients around closely, observe their daily activities, query their friends and employers and intently examine the lives they lead. The differences is that the Existential Detectives seek the solutions to the most persistent mystery of all - the one that lies at the core of reality and existence itself ... which means their investigations can get a little tricky.
Bernard and Vivian kick off their existential exploration of Albert Markovski by probing his past and present reality. Along the way, they uncover his festering conflict with Brad Stand (JUDE LAW), a golden boy executive climbing the corporate ladder at Huckabees, a popular chain of retail super-stores that wants to sponsor Albert's Open Spaces Coalition for the PR value. The Existential Detectives are convinced that Brad -- seemingly Albert's opposite -- is the key to cracking Albert's case, but then Brad turns the tables on their investigation, by hiring the detectives himself.
As Bernard and Vivian begin to dig deeper into Brad's ambition and his relationship with Huckabees' hot blonde spokesmodel Dawn (NAOMI WATTS), Albert begins to lose faith and rebels against their conclusions. Pairing up with another of the duo's clients - firefighter, tough guy and uncomprimising soul searcher Tommy (MARK WAHLBERG) - he joins forces with the Jaffes' arch nemesis, the sexy French philosopher Caterine Vauban (ISABELLE HUPPERT), who valiantly battles for the constrasting point of view.
Now, as Being chases Nothingness, Bernard, Vivian and Caterine chase one another in a wild romp through life's biggest questions to find the true answer.