In October 2003, an era transitioning into the digital age, a young and exceptionally gifted Harvard sophomore named Mark Zuckerberg, portrayed by Jesse Eisenberg, finds himself abruptly parted from Erica Albright, his girlfriend. Albright believes Zuckerberg is singularly preoccupied with the idea of joining Harvard's exclusive final clubs, prestigious yet elusive social circles. In a feeble attempt to belittle her, Zuckerberg implies that participating in these clubs will offer her, by proxy of their association, rare opportunities to mingle with elite personalities, opportunities she would otherwise never encounter. Deeply hurt and seething from this breakup, Zuckerberg hastens back to his dormitory where, in a moment of emotional tumult, he pens a scornful post about Erica on his LiveJournal blog.

This impulsive act marks the inception of Zuckerberg's infamous venture, Facemash, a website that commodifies the images of female students, dredged from Harvard's databases without consent, to fuel a hot-or-not style contest of physical appeal. The digital contraption gains immediate notoriety, captivating users with its controversial allure, but consequently causes parts of Harvard’s network infrastructure to collapse under the weight of this unexpected traffic surge, leading to Zuckerberg's academic probation for six months. While disciplinary actions against him are initiated, his deft, albeit ethically questionable program attracts the intriguing attention of the Winklevoss twins, Cameron and Tyler, both portrayed by Armie Hammer, alongside their business collaborator, Divya Narendra, enacted by Max Minghella.

The trio envisages creating Harvard Connection, an exclusive social network designed for romantic engagements among the elite Harvard community, and they invite Zuckerberg to bring his technical creativity on board. However, Zuckerberg, with the wheels of innovation already set in motion, gravitates to the idea of Thefacebook, a social platform conceptualized to weave together the intellectual bandwidths of Ivy League students across universities. He garners support from his trustworthy friend Eduardo Saverin, played with depth by Andrew Garfield, who brings a vital $1,000 to the table as seed funding. This collaboration births a website that ensnares the campus with unprecedented fervor, becoming wildly popular almost overnight.

Meanwhile, as Zuckerberg stalls the Winklevosses for six weeks, sending sporadic replies to their communications and never explicitly stating any skepticism about their project, the realization unfurls that Zuckerberg may have had no genuine intention of actualizing their vision. By January, he confidently informs them that their proposal lacks substance.

The Winklevoss twins and Narendra, disenchanted and frustrated, suspect deception as they watch Thefacebook soar to extraordinary prominence—900 subscriptions on launch day alone—breeding indignation that prompts them to seek retribution. Yet, Harvard President Larry Summers dismisses their appeals, perceiving neither punitive measures nor acknowledging the merit of their grievances.

In the battlefield of nascent tech empires, Saverin and Zuckerberg encounter Christy Lee, played by Brenda Song, who introduces slang that redefines how people interact by inviting Eduardo to "Facebook me." As Thefacebook's allure transcends Harvard, expanding to Yale, Columbia, and Stanford, friction arises between Eduardo’s commercial instincts, seeking revenue through advertising, and Mark’s vision to preserve its allure by evading conventional ad clutter. Their tensions escalate, underscored by Eduardo's unsuccessful networking excursions in New York City.

The eventual acquaintance with Sean Parker, the audacious Napster co-founder portrayed by Justin Timberlake, catalyzes a pivotal shift. Parker presents Zuckerberg with an enticing vision of immense financial potential, starkly underlined by a precedent of a misplaced opportunity at Victoria’s Secret, convincing him to reject prompt monetization efforts. He advocates for strategic patience and renames the site as Facebook, fortifying its brand identity as it burgeons through 29 campuses, reaching 75,000 users.

Saverin remains in New York, while Zuckerberg, swayed by Parker’s charm and insights, relocates operations to Palo Alto, cementing Parker’s influence over the youthful tech mogul. However, ethical challenges surface as Saverin, faced with personal accusations of animal mistreatment—a misunderstanding that tarnishes Facebook’s image—finds himself embattled and underappreciated.

Amid corporate maneuvers, Saverin's position weakens following Zuckerberg’s procurement of a substantial $500,000 funding boost from Peter Thiel, expertly played by Wallace Langham, reshuffling equity stakes to Saverin’s disadvantage. Untempered anger manifests when Saverin discovers his shares intentionally devalued to a minuscule 0.03% post a celebrated investment declaration, drastically diminishing his position against Zuckerberg’s favored confidants.

In a climactic confrontation, Saverin, incensed by perceived betrayal, vows to legally challenge Zuckerberg as his name is excised from their digital empire's founding rolls. Parker’s misconduct at a celebratory event, leading to his arrest for drug possession, provides Zuckerberg the rationale to sever ties, attempting to recalibrate integrity amidst chaos.

Ultimately, legal confrontations materialize. The Winklevoss twins press charges for intellectual property theft, while Saverin charges retaliation against unfair share dilution. Junior lawyer Marylin Delpy, transitioning adeptly between Rashida Jones' portrayal, rationalizes a settlement acknowledging that unveiling the spurious corporate origins and Zuckerberg’s uncaring demeanor could jeopardize the company's public image.

In a reflective solitude, Zuckerberg sends a digital olive branch to Albright, compulsively refreshing his page, introspecting the junction of personal and corporate losses, while history bestows hefty financial settlements to the Winklevosses ($65MM) and an undisclosed, dignified agreement for Saverin as co-founder recognition is reinstated. Facebook rises, underscored by 500 million user feats and a staggering $25 billion valuation, concluding a narrative woven with ambition, betrayal, and unrivaled triumph.