A good idea that is limited by its plot and direction. I mean if you compare it with other series of this genre like "Mindhunter" (which I watched just before this), this was a waste of time, to say the least.
There are painful plotholes and the show drags on just to keep Hannibal's crimes on going, in my opinion.
How is Hannibal magically getting into hospitals, secure homes, offices, and making so well-thought-out (also very time-consuming) murders while maintaining a full-time job, making elaborate dishes (regular and cannibal), psychologically manipulating will and keeping two of his victims locked and alive in the down-low?
Oh I know, because the show features an unrealistic, impractical plotline with a miraculously intelligent psychopath who must go on no matter what to keep the show going!
Also, how gullible can the head of the behavioral science unit at the FBI be?!
However, the show does get points for the amazing prosthetic work on the murder scenes and the case ideas themselves. The acting is good too. Those were the things consistent on this show.