One-Punch Man is a 12 episode anime starring the ultimate superhero, Saitama, who can literally defeat enemies with one punch. The anime begins with what you would call some throw-away enemies and showcases Saitama's powers. This begs the question if Saitama is really as powerful as you'd think? Yes, he is, and his powers never diminishes over the course of the anime, which keeps its key element consistent. No matter how powerful the enemy, Saitama can defeat it in one punch. The backstory to how Saitama gained his awesome powers is briefly shown which provides enough details not to leave any major plotholes and also short enough to not overstay its welcome. Basically, Saitama had always wanted to be a hero and so he ends up training himself every day, for three years, until he has gotten himself to this point.
Saitama is so strong that one punch will kill any enemy, the quirk here is that he considers himself a hero as a hobby only. As he is so powerful, throughout every encounter, he doesn't take the fights seriously. During some intense moments, he will worry more about missing a sale at the supermarket and thus not being able to save money, rather than focusing on the current overpowered monster. Needless to say, this makes for some fun scenarios. One-Punch Man has a silliness to its plot but that is what makes it so enjoyable, and brings out the charm of all the characters. The exaggerated action sequences make each one interesting and engaging.
The action sequences are like your typical anime fighting sequence, except made much better because there are no limits to what can happen, One-Punch Man has not constrained itself to make the show believable, we're just in it for the fun. A recurring theme is that the anime has a somewhat episodic take since each episode presents a new villain that pops up wanting to take over the world, and somehow Saitama gets mixed up into the thick of things and saves the day. Usually the enemies underestimate him, showcasng their powers and building up to their ultimate move, only for Saitama to casually destroy them. This can be anticlimactic since it builds up the anticipation to a huge battle, especially when previous heroes have been fighting and failing against the enemy.
You'd expect that when Saitama finally shows up, there'll be some sort of epic finale battle, but no, he just finishes the battles in a second with one punch. This is all forgiven though in the final battle of the season, which was effectively 10 minutes of sweet awesomeness. Saitama finally met someone that can hold out for longer than one punch and the end result is an adrenaline rush. All in all though, Saitama is the perfect blend of a character that doesn't care about his actions, but is so powerful and unknowingly heroic that you can't help but cheer him on and anticipating his appearance. The fact that he does have a positive effect around him, and later on, taking on slightly more of your typical heroic qualities, makes him likeable.
Eventually, One-Punch Man introduces new concepts into its world, fleshing it out a lot. These include the Hero Association, whereby all professional heroes must be registered with them, especially if you want to take credit for what you have done. A ranking system is introduced, including how some higher ranked heroes don't bother responding to threats, as the threats are not deemed significant enough for them to care. Or how some lower ranked heroes become jealous and use the ranking system to their advantage, attacking fellow heroes to further themselves up the hierarchy. Some of the more underhanded heroes manipulate the mentality of the population to go against Saitama, even though he was not obligated to save them. It evokes feelings of unfairness and vengeance from the viewer, waiting to see justice served, for Saitama to finally climb up and be recognised for his efforts.
In this aspect, we see while Saitama has no physical weakness and thus overpowered to the nth degree, he does have weak links and this grounds the character. One-Punch Man constantly switches from a style of animation with heaps of detail to a simpler style with only the outlines and cruder sketches. This feels odd at first and the simple style is mostly used in the exaggerated fighting sequences. You end up getting used to it and it doesn't detract that much. Overall, One-Punch Man is effectively 12 episodes of awesomeness. From the very first episode, you will get hooked by its premise and the execution is perfect. None of the episodes are boring, the characters and the world it presents are interesting and likeable, One-Punch Man is definitely a fantastic anime that you should watch.
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