During the final episode pre-screening event on Friday, it was announced that Double Decker! Doug & Kirill TV anime will get three extra episodes. Titled Double Decker! Doug & Kirill: Extra, the three episodes will be streamed via Bandai Channel and other streaming websites between February and April 2019. The Blu-ray and DVD for the extra episodes will also be released on May 24, 2019.
 
(Source: MAL News)

The city state of Lisvalletta. Two suns rise above this city, and the people here live peaceful lives, but in the shadows crime and illegal drugs run rampant. Among them is the dangerous, highly lethal drug "Anthem" which casts a dark shadow over the city. The SEVEN-O Special Crime Investigation Unit specializes in cracking down on Anthem. This unit operates in two man "buddy" teams in what's called the "Double Decker System" to tackle the problem. Doug Billingham is a seasoned investigator, and joining him is Kirill Vrubel, whose abilities are mysterious and unknown. 

(Source: Crunchyroll) 

The first episode was distributed online through Bandai Channel and Crunchyroll on September 3, 2018. TV broadcast begins September 30, 2018.

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