Death Note, Vol. 4 by Tsugumi Ohba

[Viz] When Light Yagami finds a notebook giving him power over death, will he use it for good—or evil? Light Yagami is an ace student with great prospects--and he's bored out of his mind. But all that changes when he finds the Death Note, a notebook dropped by a rogue Shinigami death god. Any human whose name is written in the notebook dies, and now Light has vowed to use the power of the Death Note to rid the world of evil. But when criminals begin dropping dead, the authorities send the legendary detective L to track down the killer. With L hot on his heels, will Light lose sight of his noble goal...or his life? With two Kiras on the loose, L asks Light to join the task force and pose as the real Kira in order to catch the copycat. L still suspects Light and figures that this is the perfect excuse to get closer to his quarry. Light agrees to the plan in order to have free access to the task force resources. But when Light manages to contact the new Kira, he discovers that hi