Scott Adkins' new action movie Castle Falls drops a reference to his signature role in the Undisputed martial arts series. English actor Adkins is known for a variety of martial arts roles. However, it was his performance in 2006's Undisputed II: Last Man Standing that really cemented his status as a star. As Castle Falls proves, the movie remains relevant to this day.

Directed by and co-starring Dolph Lundgren, Castle Falls battled the effects of the COVID-19 pandemic very early, being subject to a shutdown on its very first day of production before being able to resume months later. For fans of Adkins and Lundgren, Castle Falls presents a very contained story with plenty of race-against-the-clock action. In Castle Falls, Adkins plays Mike Wade, a former MMA champion working a temp gig at an old hospital scheduled to be demolished. On the day of the building's destruction, he discovers three bags full of millions of dollars hidden inside. However, he soon finds himself battling a gang of criminals arriving to retrieve the stashed money for their jailed boss, while corrections officer Richard Ericson (Dolph Lundgren) also intends to steal the money to save his dying daughter.

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Before the main conflict kicks in, Castle Falls slips in a clever in-joke to Adkins' portrayal of the very tough Boyka from the Undisputed franchise. While clearing debris out of the building ahead of its demolition, Mike strikes up a friendship with fellow worker George (Vas Sanchez), who eventually recognizes Mike from one of his fights. George commends Mike on his fight against one particular opponent, saying "You knocked the hell out of the mean, ugly guy with the mohawk!", with Mike replying, "Oh yeah, that guy! Real nice piece of work!" This is a sly reference by Castle Falls to Adkins' portrayal of the mohawked Russian prison MMA fighting machine Yuri Boyka, aka The Most Complete Fighter in the World.

Boyka Undisputed pic

Adkins first debuted as Boyka in Undisputed 2: Last Man Standing, beginning as an antagonist set to fight the wrongfully imprisoned George "Iceman" Chambers, played by Michael Jai White. Undisputed 3: Redemption transitioned Boyka into an anti-hero protagonist, competing in a tournament to win his freedom while working around his bad knee from the last movie and facing attempts to rig the tournament in favor of the sinister Dolor (Marko Zaror). Boyka: Undisputed gave its hero his greatest challenge yet, with Boyka inadvertently killing an opponent in the ring, and competing in a series of fights to free the fighter's widow from her debt to a Russian gangster.

While the franchise had a middling start with the first Undisputed in 2002, Boyka became the definitive centerpiece of the series. Adkins' portrayal of Boyka directly led to him becoming one of the biggest modern martial arts stars, and he also later launched his popular YouTube series The Art of Action, featuring interviews with other big players in action movies from Ong Bak's legendary Tony Jaa to Chad Stahelski, director of the John Wick series. With Adkins boarding John Wick: Chapter 4 under Stahelski's direction, it's testimony to the impact he's had on the action movie world that first began with his performance as Boyka in the Undisputed series. That wasn't forgotten by Castle Falls either and the movie's shout-out to The Most Complete Fighter in the World shows how much of an unforgettable impact Boyka has had.

NEXT: Scott Adkins' Personal Favorite Action Movies Of His Own