Ryuk (Japanese: リューク, Hepburn: Ryūku) is a fictional character in the manga series Death Note, created by Tsugumi Ohba and Takeshi Obata.

He is a Shinigami that drops a Death Note, a notebook that allows the user to kill anyone simply by knowing their name and face, into the human world to find relief from the boredom of his own realm.

It is picked up by Light Yagami, a bright high school student who uses it in an attempt to create and rule a utopia cleansed of evil, with him at the helm as a "god".

In the American live-action film adaptation Jason Liles played the character in costume while Willem Dafoe provided the voice acting and facial motion capture.

Obata said that he encountered difficulty while drawing Ryuk in the pilot chapter since he did not "have a good handle" on the "bone structure of his face."

Obata describes Ryuk's face as appearing different between the pilot chapter and the actual Death Note series.

[3] The director of the American adaptation, Adam Wingard, wanted to do the opposite of the Japanese films and have an actor on set portraying Ryuk as much as possible.

"What we did was basically cut out the on-set creature's face and had Jason wear these red LED glasses, so at least we could see a representation of his glowing eyes, knowing we were going to replace that later with some CGI, and then voice it over with Willem."

He deliberately writes the instructions inside the front cover (in English, which he assumed to be the most popular language in the human realm) so people would understand its purpose.

His skin is blueish gray, or a purplish color, his limbs are abnormally long, and he has bulging yellow eyes with black irises (red in the anime); in the films, he is represented by CGI.

He enjoys seeing Light overcome the various challenges put to him, and often waits until the worst possible moment to inform him of a certain aspect of the Death Note just to get a laugh.

[8] Two years later, Ryuk berates another shinigami in their attempt to replicate his success with Light by giving their own Death Note to a "weak" human.

Subsequently, in 2019, Ryuk returns and the pair sell the Death Note to the U.S. President (the text does not call him by a name, though Hannah Collins of Comic Book Resources stated "the uncanny likeness to the divisive political figure is hard to miss.

"[9]) for $100 trillion, to be divided evenly amongst every Japanese bank account holder under the age of 60, before the human relinquishes (and memories of) his Death Note to Ryuk.

[10] In the anime adaptation, Light does not ask for Ryuk's help and manages to escape the warehouse thanks to Teru Mikami's suicide distracting everyone else.

In the fourth film, Death Note: Light Up the New World, Nakamura Shidō reprises his role as the voice and motion capture of Ryuk.

The leader of Death Note task force, Tsukuru Mishima witnesses the whole thing and kills Mikami and takes his notebook.

Actor Willem Dafoe provided the voice acting and motion capture of the character's facial elements in the American adaptation.

[laughs][16] While praising Obata's artwork for the series, Zac Bertschy of Anime News Network singled out Ryuk as the prime example; describing him as "a grotesque hulking beast, the kind of thing most people would probably think of when they're asked to imagine what a grim spectre of death would look like.

"[19] Pepirium described Drummond's voice as "excellent" and that this makes it "hilarious" to watch "Ryuk and his never-ending grin giggle at the events he put into motion.