By and large, the last decade has been, with a few exceptions, a dire one for blockbuster filmmaking. And that’s exactly why 2014’s Edge of Tomorrow, 10 years after its release, remains a breath of fresh air. Taking equal inspiration from pulp science-fiction, the Groundhog Day-esque time loop subgenre, and the structure of a video game, Edge of Tomorrow mixes all of these disparate elements into something clever and exciting. It’s also unexpectedly a dark comic delight, with Tom Cruise poking fun at his action star persona and Emily Blunt proving a fantastic foil.

Although only having a mediocre run at the box office, the film has slowly but surely developed a cult following, and fans (and the stars) are eager to bring a sequel to light. But there’s a great irony to how many heralded Edge of Tomorrow as an original IP upon its release in summer 2014, as it was actually based on a 2004 Japanese novel. That said, despite the similarities the film shares with Hiroshi Sakurazaka’s All You Need Is Kill, the two differ significantly in the details, to the point that even calling Edge of Tomorrow an adaptation feels like a stretch.

How Does Edge of Tomorrow Differ From the Book?

Both Edge of Tomorrow and All You Need Is Kill revolve around a soldier killed in a battle against an extraterrestrial race, only to get stuck in a time loop and relive the same day repeatedly, allowing him to find new ways to gain an advantage on the battlefield. That’s where the similarities between the two properties stop.

First and most obviously, the protagonists have significantly different characterizations. All You Need Is Kill focuses on military recruit Keiji Kiriya, who’s eager to defend his country against an alien race known as the “mimics,” but he dies on his first mission. In contrast, Edge of Tomorrow sees Tom Cruise playing Major Bill Cage, a public relations official who’s conscripted to fight in the war against the mimics. Being an inexperienced coward, Cage tries to get his orders rescinded, but he’s forced into battle and killed almost immediately.

Things differ even further from here. Edge of Tomorrow next sees Cage getting help from war hero Rita Vrataski (Emily Blunt at her best), who’s also trapped in a time loop. Through her training, Cage becomes a stronger soldier and an overall more heroic figure, getting gradually better in each cycle. In contrast, Keiji Kiriya doesn’t seek any external training, and his growing prowess in combat is painted specifically as his ability to learn from his previous mistakes.

The two stories also differ slightly in their portrayal of the Mimics. As portrayed in the book, a Mimic on the battlefield, known as a “Server,” collects information on a day’s conflict with help from “Antennae” Mimics before using the data to reset the day and gain an advantage during the next loop. The film sees the Mimics fighting more akin to a traditional army; Alpha Mimics function as generals in battle, while their superiors, Omega Mimics, reset the loop if one of the Alphas is killed. While many Servers are allowed to exist, there is only one Omega Mimic, giving Cage a much clearer endgame on how to break the loop.

Edge of Tomorrow Has a Happier Ending Than the Book

But the biggest difference between Edge of Tomorrow and All You Need Is Kill is probably in their endings. Even though Keiji mostly trains himself throughout the time loops, Rita Vrataski is actually still a supporting character in All You Need Is Kill, and she and Keiji still team up to break the loop once and for all during the climax. However, even after they kill all the Servers and Antennae, they still find themselves in yet another loop.

Rita comes to a horrible realization — as a result of staying in the loop too long, both of their brains have been modified and now function like the Antennae Mimics. This means the loop can only be closed if one kills the other before destroying the final Server. The two reluctantly fight, and Keiji ultimately proves the victor, killing Rita before finally closing the loop once and for all. While the military celebrates him for his actions, he remains haunted by the sacrifice he had to make to win the war.

In contrast, Edge of Tomorrow has a much more crowd-pleasing endgame (despite the initial plans otherwise). After several loop iterations, Cage and Vrataski manage to locate the Omega Mimic underneath the Louvre in Paris. As they fight their way through enemy forces, knowing they’re effectively on a suicide mission, they find the Omega guarded by a particularly vicious Alpha, who kills Vrataski and severely wounds Cage. However, with his final breath, Cage drops a bag of grenades onto the Omega, destroying it for good, and as he dies, he’s bathed in the Omega’s blood.

This allows him to loop one last time, sending him back to the day he was ordered onto the battlefield, but he and his regiment learn that all the Mimics have died following an energy surge in Paris. No longer the total coward he was at the start, Cage seeks out Vrataski, and while she doesn’t remember their time together, it’s clear that he has a lot to tell her. While it still leaves a couple of lingering mysteries here and there and room to continue the story, it also satisfyingly ties up most of the loose ends.

Edge of Tomorrow Stands on Its Own Amazingly Well

While Edge of Tomorrow and All You Need Is Kill diverge so heavily from each other to the point where it’d even be a stretch to call the former an adaptation at all, both works stand on their own and work amazingly well on their terms. The novel’s brutal honesty in depicting the nature of heroism and the sacrifices necessary to achieve victory is a perfectly valid direction to take its premise, as is the old-fashioned, crowd-pleasing fun that Edge of Tomorrow opts for.

If anything, the film serves as a testament to how not being beholden to faithfully adapting source material can actually benefit a creative team, as it holds up 10 years later as one of the most relentlessly entertaining blockbusters in recent memory. Edge of Tomorrow is streaming on Netflix.