First I am a real reviewer and a big fan of 80's action movies.
Now the plot is easy to follow. Boyka is back, commits an atrocity and needs to fix what he has done to redeem himself. That is all you need to know. The movie does have some heart during his redemption. A lot of flash, but also moments where you feel for Boyka and his journey.
I do not know the director's work prior to watching this, but he did a great job of filming action scenes. A lot of movies break the action up by changing the camera angles. This movie tones that down and lets you watch the action taking place.
I miss the days of real action movies. I will sound repetitive but this movie has lots of action, fights, fast moving plot and great choreography.
B-Movie or not, the movie is a 9.5. I am a fan of the Undisputed series. Scott Adkins is excellent and the bad guys are bad, and the good guys(Adkins) aren't perfect. The movie has heart and has a great pace. It's not slow, and is very entertaining throughout. One of the best modern fighting movies and dare I say the best fighting franchise if that is a genre. A must watch is my opinion.
Yuri Boyka Says Bring Me Your F#ing Champion.