Jerry Falk, portrayed by Jason Biggs, is a young writer living in the bustling heart of New York City. He finds himself in a relationship with his girlfriend, Brooke (played by KaDee Strickland). Things take a turn when they encounter Jerry's friend Bob, who is dating Amanda, an opinionated and captivating woman who catches Jerry's attention. Intrigued by Amanda's strong personality, Jerry feels an undeniable connection due to their shared interests in music, art, and literature.
In a bid to impress Amanda, Jerry disguises his true nature—despite his aversion to mosquitoes, he contemplates an adventurous trip to the Amazon, and he feigns enthusiasm for snakes, despite scarcely venturing beyond the city limits. During one of their outings, Amanda confides that she's taking diet pills that heighten her sexual interest. As their relationship develops, Jerry becomes infatuated with Amanda, eventually leading to an affair that complicates his life further.
While grappling with his romantic entanglements, Jerry remains entangled in a fruitless therapy routine with his psychiatrist, who fails to guide him properly and suggests he should continue therapy instead of pursuing a promising job opportunity in Los Angeles. Amanda eventually leaves her boyfriend Bob Stiles (played by Jimmy Fallon) for Jerry, but even as their physical relationship flourishes, Jerry struggles to be honest with Brooke, who eventually discovers the truth and leaves him after noticing bite marks he foolishly claims are from an accidental fall.
Amanda's unpredictable nature frustrates Jerry, as she arrives late to their dates and exhibits disarray in her life. An aspiring actress, Amanda shamelessly consumes Jerry’s resources, including his food, and brings her mother, Paula (portrayed by Stockard Channing), into their home after Paula's recent breakup. Amid mounting chaos, Amanda forces Jerry to make adjustments to accommodate her mother, further straining Jerry's patience and stability.
To navigate this tumultuous situation, Jerry seeks counsel from Woody Allen, an aging comedian named David Dobel, who becomes a mentor to Jerry. Their conversations in the park are largely one-sided, with David imparting melancholic wisdom while Jerry struggles to establish himself as a writer. Meanwhile, Jerry's agent, Danny DeVito as Harvey Wexler, presses him to extend their contract, adding to his mounting stresses.
As the rift between Jerry and Amanda grows due to her increasingly erratic behavior, she declares that they should rekindle their earlier romantic nights, but soon proves unattainable as medical issues arise, prompting visits to a doctor. Conversations between Jerry and the cab driver reflect on love and relationships, repeatedly reiterating that "It's like anything else."
Despite Jerry's frustrations and misgivings regarding his life choices, Amanda unexpectedly introduces him to her friend Connie, setting off more waves of jealousy and doubt. Jerry starts to spy on Amanda, encouraging self-destructive tendencies. As Jerry confronts the reality of Amanda's infidelities with a fellow actor, his mental health deteriorates, further exacerbating the strain in his life.
As his relationship with Amanda teeters on the edge, and his personal and professional lives dissolve into chaos, Jerry is forewarned by David about the detrimental effects of clinging to toxic relationships. Ultimately, Jerry is left with the decision of whether to leave it all behind in pursuit of a new life in Los Angeles, while realizing that the disarray surrounding him is often a reflection of his own insecurities and fears. Ultimately, the unbearable weight of his romantic entanglements catches up with him, leaving him shattered as he witnesses Amanda's infidelity firsthand in a cab, laughing with the doctor who had treated her.
