In a crucial turning point in their lives, best friends Anthony Padilla and Ian Hecox find themselves facing a moment of truth, both literally and metaphorically. Residing in Ian's family home, Anthony juggles his responsibilities as a pizza delivery man, while Ian immerses himself in the vast world of YouTube, hunting for viral treasures. Their lives take a comedic twist during an embarrassing episode at the Game Bang arcade, where a group of street-savvy kids mock them due to Anthony's vibrantly painted pizza car.
Their situation worsens when they stumble upon an old video from their high school graduation, showcasing Anthony's ill-fated attempt to impress Anna Reed with an audacious backflip—an effort that spectacularly backfires, resulting in an embarrassing face-plant and a microphone mishap. To make matters worse, they realize that their five-year high school reunion falls on the same day, and this cringe-worthy footage could ruin Anthony's chances of rekindling his crush on Anna.
In a fit of determination, the duo sets their sights on YouTube headquarters, where they encounter receptionist Stephanie and CEO Steve YouTube. Steve reveals the shocking truth: to amend the situation, they must journey inside YouTube itself and rectify the video from within. Persuaded by Anthony’s tenacity, Ian reluctantly joins him on this audacious adventure, armed with futuristic phones embedded with an artificial intelligence named Diri. Together, they enter a portal hidden away in Steve's closet and tumble into a whimsical and surreal universe filled with an array of YouTube videos.
However, their original plan quickly crumbles as they become separated. While Ian loses himself in the alluring "Butt Massage Girl" video featuring his crush, Anthony finds himself fleeing a furry-themed party, searching for guidance from none other than Steve Austin. As he navigates through this bizarre realm, Anthony discovers that Anna's feelings might not be as one-sided as he believed. Meanwhile, Diri guides Anthony back to Ian, who is indulging in a massage session within the confines of the Butt Massage Girl video. This confrontation forces the friends to reassess their priorities amidst the digital turmoil.
As the embarrassing video continues to unfold, a furious Anthony learns that Ian was the mastermind behind its creation and dissemination. With pent-up emotions bubbling to the surface, Ian finally channels his frustration at Anthony's transformation into a mundane version of himself, leading to a heated exchange between the two. Their verbal spar escalates into a physical clash, spilling over into various other videos, culminating in their return to the original cringe-worthy footage. In a bid to make things right, Ian intervenes to prevent Anthony's humiliation, but this move inadvertently results in a confrontation with his past self.
As chaos reigns and more students join the fray, Steve YouTube reveals his true nature as Diri, disclosing that sending them to the digital world was part of his devious plan to ensnare them within YouTube indefinitely. Frightened by their dire situation, Anthony and Ian embark on a desperate race for freedom, sprinting through their video history while Steve hurls futile obstacles in their path. Just as despair begins to settle in, an unexpected hero appears: a bear launches a surprise attack on Steve, granting Anthony and Ian the perfect opportunity to escape.
As they return to reality, the consequences of their escapade unveil an alternate timeline where they have skyrocketed to fame. They bask in the limelight of celebrity status, having met the President of the United States and created their own TV series, even making waves on Broadway. Ian finds himself dating Butt Massage Girl, while Anthony, surprisingly, is encircled by a host of admirers—30 girlfriends, to be exact, all of whom he chooses to reject. Their newfound success leads them to a lavish mansion, living luxuriously with Ian's parents.
As their high school reunion approaches, Steve YouTube has rebranded himself to You-too-bay, and has taken over Anthony's pizza delivery job, while Jenna Marbles has assumed leadership at YouTube. On this nostalgic journey back in time, Butt Massage Girl joins them, adding to the chaos. When the reunion finally unfolds, an unexpected twist captures everyone's attention: Anthony's ascendant star power positions him at the epicenter of the event, reigniting his pursuit of Anna. What surprises him most is that Anna has secretly harbored feelings for him all along but felt intimidated by their contrasting worlds.
Inspired by Ian's exuberance and a motivational vision of Austin, Anthony executes the daring 'Magic Pocket Slave Monsters' routine with newfound confidence, thrilling the audience. This dazzling performance ultimately wins Anna over, culminating in a heartfelt kiss that leaves the onlookers speechless. Offstage, another twist unravels as Butt Massage Girl and Anna connect, revealing a shared secret that has Ian caught up in a whirlwind of excitement.
