You know how, even after you clock out, your 9-to-5 still lingers in your head? Imagine your life being only 9-to-5, all the time. In the world of “Severance,” it is.

“Severance,” an Apple TV+ production created by Dan Erickson, just concluded its stellar first season two weeks ago. It was unsurprisingly renewed for a second season after a wave of critical acclaim. Currently, it sits at 98 percent on Rotten Tomatoes.

“Severance” is a sci-fi thriller led by Adam Scott as Mark S., a man freshly promoted to manage a group of workers who, like himself, have had their brains surgically divided between their work and home lives. At work, they have no idea who they are on the outside. At home, they have no idea who they are on the inside. The series focuses on the Macrodata Refinement department, comprised of the “innies,” which is what severed workers are called while they are at work: Mark S., Helly R., Dylan G. and Irving B. and their bosses, Mr. Milchick and Harmony Cobel. When a former colleague of Mark’s appears to him outside of work, somehow remembering everything despite the severing process, their lives are thrown into turmoil as the innies slowly reconcile with their jobs and search for pieces of their lives in the outside world, despite innie Mark not knowing that his coworker visited him in the outside world at all.

Though it may sound a little convoluted, it really isn’t. Despite being a show you really have to pay attention to, “Severance” has an extremely tight script — by the end of the season, every loose thread is connected to something else, weaving a complicated web of connections between characters and ensuring multiple jaw-dropping cliffhangers. It’s all big swings with huge payoffs.

While the basic idea of “Severance” could sound overused (“Work is hell”), it’s so far from it. It’s a nightmare in a dimly lit, garishly carpeted office that transcends time period. It’s a show about how work affects our lives and how much of ourselves we dedicate to it. It’s a show teeming with sadness, with depression, with a study of how we grapple with loss and how we torture ourselves as we grieve.

Before we get into the technical aspects and performances of “Severance,” we really need to talk about the set design. The innies work for Lumon Industries, separating “good data” from “bad data” day in and day out with no idea what they’re actually doing. They work in a room that, width-wise, is extremely spacious, but their desks are clustered together in a group of four. The ceiling is low. The walls are some weird sterile white paneling. The wall-to-wall carpeting is hideously green. It’s claustrophobic. It’s tight. Outside of their office, the hallways are labyrinth-like, and the innies themselves don’t even know how to navigate them. The entire severed floor of Lumon Industries lacks air, which makes sense, considering it’s probably underground.

Outside of Lumon Industries, in the town of Kier, named after Lumon Industries’ founder, it’s dark and cold. The series is set in the winter somewhere in Pennsylvania, so it’s slushy and gray. Even during the daytime, which we rarely see, it’s overcast and depressing. Mark’s home, identical to all of the others in his empty neighborhood of employee housing, should be cute with its cookie-cutter design, but it isn’t. It’s dark and Mark’s sadness lingers around every corner in every shadow, making the whole thing feel worse. The set design of the show is a triumph, a master class in how to make something innocuous like a few desks look truly sinister.

Those feelings — claustrophobia, tension, depression — are not just produced by the set design. Directors Ben Stiller and Aoife McArdle are to thank for that too. Stiller directed the bulk of the show, proving to be really masterful behind the camera with the way he created tension and a terrifying working world. Both Stiller and McArdle are impressive directors who manage to turn a world that should be average and bleak into something unnerving and scary. Seemingly effortlessly, they turn an office building into a horror movie.

Of course, the “outies,” which is what the workers are called on the outside, don’t really understand that their working lives are horror movies. For the innies, it might be the one thing they do understand. The innies are like children: inexperienced and clueless. They know macrodata, and that’s about it. Even their name makes them sound childish: innies. They don’t know how to cope with emotion, which is fitting, considering most people take severed jobs to avoid the emotions of their outside lives. They don’t even know how to fight like adults, evidenced by the suspicious card found in the Optics and Design department or the fact that one character bites like a child when he fights another. In episode seven, “Defiant Jazz,” the innies hear music for the first time. They think that deviled eggs and melons are a wondrous feast. They’re green. They’re clueless. “Severance” is about emotions — how we deal with them, how we avoid them, the ways we suppress them — and the innies are emotionally immature to the highest degree.

The cast is full of incredible actors who deftly toggle between their characters as innies and outies. Scott stands out as he effortlessly shifts between innie Mark and outie Mark. As Mark rides up the elevator at the end of the workday, becoming his outie self somewhere around halfway up, it’s like Scott has suddenly gained more lines around his eyes, more grief in the set of his mouth, more weight on his shoulders. It’s incredible to watch, and it’s also deeply moving. All of the innies — including those played by Britt Lower, Zach Cherry and John Turturro — handle their shifts excellently, but Scott is really something special to watch. The characters who exist solely in the outside world — particularly Mark’s sister Devon, played by Jen Tullock, and his brother-in-law Ricken, played Michael Chernus — are acted just as fantastically. While it’s nearly impossible to pick a favorite, it’s fair to say that Chernus delivers a hands-down hilarious performance as an absolute granola self-help author who takes himself entirely too seriously. Chernus proves that “Severance” is more than wall-to-wall drama and thriller: it’s funny, too, and perfectly absurd.

“Severance” really has no flaws. If it drags at one moment, it picks back up in an instant. It asks questions of the viewer and demands that you pay attention, but that’s good. It’s pretty in line with the theme of it all to make us work for it, right? Besides, “Severance” is really worth all of that work. It’s smart and funny and also heartbreakingly sad, and, at a tight nine episodes, perfect to watch and immerse yourself in as you procrastinate the rest of the work for your semester.

Rating: 5 out of 5 stars