Released in 2006, Undisputed II: Last Man Standing is a sequel to the first Undisputed film in 2002. The film stars Michael Jai White, Scott Adkins, Ben Cross, and Eli Danker. The plot starts when an American named George "Iceman" Chambers is framed for drug possession while visiting the Russian Federation for some boxing fights. Imprisoned without anyone knowing where he is or what the circumstances are, Chambers is forced to weather it out. During his time in prison, he unravels an illegal underground-style full-contact mixed martial arts competition that is currently ruled by a prisoner named Yuri Boyka. The prison officers manage the fights and make huge side-bets to gain potential personal profit, which is likely at the expense of the inmates.
Discovering the illegal arena, Chambers is approached by the jail warden and his legal adviser, offering him a deal for his freedom. The deal states that if Chambers goes on one match with Boyka, he increases his chance of getting an expedited appeal and premature release. He quickly refuses the deal.
But as time went on, Chambers experienced tremendous amounts of police brutality and was given degrading physical chores involving the prison's sewer lines. Unable to take more of the abuse, he is forced to agree to the deal. During the abuse, he is rescued by a mysterious crippled prisoner named Crot, who is later revealed as a former military soldier, martial arts specialist, and the trainer of Boyka.
As the match date nears, both fighters train to their limits. Chambers focuses on his boxing skills while Boyka trains with a series of painful kicks, throws, and grappling combos that will humiliate and knock out his foes. But before the fight, Boyka's friends instruct Steven, Chamber's cornerman, to mix a sedative drug on Chamber's water during the match. Forced and afraid to receive his own beating, Steven reluctantly agrees.
On the first round, Chambers is shocked as he is barraged by a variety of attacks, yet manages to hold himself through the round and was even able to land some good sharp punches. As they prepare for the second round, Steven slips the sedative on Chamber's water before giving him the drink. This causes Chambers to lose composure and focus on the second round, making it effortless for Boyka to unleash a flurry of attacks.
Later on, Chambers asks for a rematch and makes a deal with the prison officers that he can beat Boyka for his freedom. He learns a new submission technique from Crot, which he later uses to make Boyka tap out.