Desmond, a habitual slacker known for his chronic tardiness, works at Ammotech, a prominent global weapons manufacturing company, which is currently embroiled in a strategic merger. His boss, Adam Nusbaum, frequently reprimands him and warns that he needs to improve his performance, especially since some colleagues have already been dismissed amid ongoing layoffs. The atmosphere at the office is tense, with everyone preparing for uncertain times ahead.
One day, after attending a company seminar with his friend and crush, Samantha, Desmond notices pallets of drinks being delivered and unpacked in a corridor. Shortly afterward, he's summoned back to Adam's office, only to discover that Adam has committed a shocking act—killing a coworker. This revelation triggers chaos, and Desmond quickly escapes, especially after his report, which contains clear spelling and grammar mistakes, is harshly criticized by management.
The situation spirals out of control when colleagues, impacted by an experimental energy drink, begin to behave violently and irrationally. Some employees, including members of the accounting and advertising departments, start to act erratically after consuming the beverage. Desmond tries to call for help, but the company’s strict policies prevent him from dialing out without supervisor clearance, trapping him and others inside the building. He soon finds Samantha, who is already experiencing violent episodes due to the effects of the energy drink, and tries to intervene, but she has to be restrained as her behavior becomes increasingly unpredictable.
As the chaos unfolds, Pat, an operator, along with other staff members, get caught up in the madness. The energy drink turns into a catalyst for violence, leading to the deaths of department heads, including the head of advertising. Desmond's friend Mourad, who remains sober, finds them hiding in a closet, and together they attempt to escape. Their escape plans are thwarted when security triggers an alarm by breaking an external window, adding more hurdles to their dangerous situation.
The group manages to find refuge in the HR department, where they encounter Edward. Using the intercom system, Desmond disguises himself as Adam to convince Edward to come out. They quickly arm themselves with makeshift weapons and mount a daring assault on the CEO, Franklin Gantt, in his office to uncover what was added to the Zolt energy drinks. Franklin explains that the energy drink was designed to enhance alertness, but the first batch was sabotaged by a former scientist with a grudge, who intentionally made the staff violent.
Adam then demands that Franklin lift the building’s security system so everyone can escape. His followers break into Franklin’s office, killing him and Edward, and proclaim their desire to leave the company behind. Adam leads his group to the ground level, using Franklin’s fingerprint to disable the security system. Meanwhile, Nicholas Frohm, a colleague, admits that the toxin in the energy drinks was altered to meet tight deadlines, and that an antidote exists.
Desmond and Mourad rush to retrieve the antidote to save Samantha, but their actions are caught on CCTV. A fierce fight ensues as they attempt to distract the enraged staff with more energy drinks, while Mourad manages to obtain some of the antidote. During the climax, Adam confronts Desmond, mocking his lack of contribution to the company, and is ultimately blown to bits by a land mine in a dramatic showdown.
In the final moments, Mourad, Samantha, and Desmond shoot their way through the remaining violent employees and make a frantic run from the building’s front exit. Samantha then shares a heartfelt moment with Desmond, kissing him and urging him not to wait so long in the future to express his feelings. As the chaos subsides, emergency services arrive to contain the fallout, leaving Desmond and Samantha to face the uncertain future together.
