(at around 30 mins) At the scene of a mass killing in Japan, a police officer (played by Masi Oka) comments that the crime does not make sense as "the Nakamuras and the Inagawas have had a truce for over ten years." Hiro Nakamura was the name of Oka's character in Heroes (2006).
Ryuk:
Shall we begin?
(at around 10 mins) When Light first writes in the Death Note, Ryuk hands him a pen and you hear the distinctive click of a retractable roller-ball pen. Cut to Light writing Kenny's name and he's using a fibretip fine-liner. Then when Light is writing the 'How' hes using a roller-ball again.
Near the end of the closing credits, Ryuk can be heard laughing.
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