The Boys begins with a young man and his girlfriend. The girlfriend is accidentally destroyed by a super-fast hero who, without sincere remorse, runs off after the young man realizes what just happened.
People expect the young man to move on, but he cannot. What happened to his girlfriend, the superhero demolishing her just because she was in his path, a person who did nothing wrong to him, the young man could not let this slide. That man was named Hughie, the true hero of the story.
As the story progresses you follow Hughie's desire for justice and the events that he endures because of his ambition. Along comes the beautiful/stunning Annie, who could... I guess fry people with light. It is kinda confusing, but she can essentially clear a room just by exploding herself with a burst of energy.
Hughie and Annie eventually cross paths after Annie goes through a seriously upsetting event with the "Seven" a superhero squad that recruited her. One of the team members of the Seven is removed after Annie fights back and makes it obvious what happened to her at the hands of one of the Seven's top members (debatable really).
As far as quality of the show, it is through the roof. The production value, the costumes, the unique characters, and depth to them, it goes beyond what I am used to watching.
My favorite character so far is called Homelander. Homelander is essentially this dimension's version of Superman, super strength, flight, laser eyes, the whole thing. Essentially Homelander was once human, but he was recruited, and put in a lab, which naturally messed up his psyche and explains pretty much everything he does in the show, including his obvious god-complex behavior.
Out of every superhero TV show I have seen, The Boys is the best. The only show that would compete with this might be the animated Justice League (which is not that close) and WandaVision (a pretty darn good show too).
Overall, I do not want to ruin too much, but expect a lot of content designed exclusively for grownups, a lot of content derived from real life and a whole lot of disappointment because they do not always let who you want to win, win. In fact, it is often the opposite.
There is also a show on Amazon called "Invincible" that people might want to compare to this. Thing is, The Boys is way better. Comparing Invincible to The Boys is like comparing The Witcher to Game of Thrones. Come on.