This anime is by far one of the smartest and most suspenseful ones I have seen. It is like a mix of the Hunger Games and Death Note, where any "friend" can betray you in the blink of an eye, and you never know what a character is truly thinking until the very end when all is revealed. The whole show is very unpredictable, shrouded in mysteries which seem at first impossible to solve but all makes sense in the end, which is incredibly satisfying. The plot twists, puzzles, psychological elements and characters are brilliant, and the hardly comprehensible synopsis and the low ratings do notdo it any justice at all. This will be of great interest to anyone that enjoys detective stories, intellectual puzzles or even solving math problems.

This anime is about an university lad that risks his life to find his girlfriend in what seems like an alternate universe which (trying to avoid spoilers here) might not be so alternate after all. There, he goes through a series of dangerous real-life puzzle games versus other contestants, usually strangers, in order to advance through this strange new world. These games test not only mental agility but physical ability - failure to run fast enough, shoot accurately or use a weapon efficiently will mean certain loss. Players exist in both worlds, so drama can ensue not just in the game but in either universe. Each player is ranked on a points based system, so dying in a game may not mean certain death in the real world, but having a negative score will.

His girlfriend is a bit of a sap, but other than that all the characters are very intelligent, focused and relatable to some degree. Each episode challenges you to think and the way that the characters, especially the main character, solves the problems never fails to impress.

My only complaint is that some (only a few) of the deductions made by characters can seem a little far fetched, however this doesn't confuse the storyline. As of yet after reading the manga I haven't detected any unfilled plot holes.

If you like drama, life and death suspense situations, clever puzzles and plot twists and shocking betrayals, then this is the anime for you.