This is one of the most engaging thriller anime i have ever seen EVER. How could that be? Let me count the ways...
Story - The first story arc involves an extremely intelligent high schooler (Yagami Light) with the power to kill against the best detective the world has to offer (only known to the world as "L"). Its a classic story of cat and mouse, one consistently outwitting the other with cunning tactics and sly tricks. Each episode also leaves the viewer with just enough suspense to keep you wanting more EVERYTIME! Not only that, like any good detective show (i.e. CSI), both main characters love to tell the viewers exactly how they pull off plans and show of their intelligence.
Animation its very good and smooth no stuttering. The whole screen seems to have a purpose. The mood of the whole show is dark and shadowy theme which is why its predominantly black, night scenes, dark lit rooms, clothing, etc. The great thing about having the main theme as black is that they can portray certain emotions easier (i.e. snow representing innocence, apples being bright red, protagonist = white, antagonist = black, etc.) my only gripe is mostly dark... you'll understand when you start watching.
Without a good storyline and good animation, you might as well throw the characters out the window since you wont relate to them. But thanks to the outstanding story and very good animation, the characters are some of the best in the business. You'll really relate to the characters point of view, thanks mainly to their thoughts being spoken aloud. They take "getting inside their head" to a whole new level.
Overall this is one anime that you wont forget for a long LONG time...