Sennyû tantei Tokage (2013)

Arrest rates for the police have dropped significantly. Believing this calls for desperate measures they have against the rules begun to hire a private detective for cases which require undercover work: Toru Oribe, nicknamed Tokage (the Lizard). Unsociable yet brilliant, Tokage is a former cop whose leaving the force is one of the main reasons why arrest rates have dropped, and he smoothly infiltrates criminal circles by taking on various identities. However, his former colleagues treat him with suspicion and resentment over a case two years ago, when he supposedly left his partner to die.