Roday and Hill are probably the best comedic duo in modern history. The way they play off of one another means that you are going to laugh at something in every episode, and you can't that about, well, almost any other television show in modern history.
But, it goes beyond that, the show makes you feel bad for Maggie Lawson, it really does. She has her moments. She has her one liners, she has her laughs, but she is the straight man in a cast that's hysterical. She has to keep a straight face and be the relatable character when she's surrounded by hilarity.
That has to be hard, especially given that her partner is his own kind of funny. The M.E. is hysterical, and even Bernson has his moments.
Start to finish the series is hysterical.