Based on a mystery love comedy light novel series written by Nigo Juu and illustrated by Umibouzu. Media Factory have published the series since November 2019 under their MF Bunko J imprint.
The first part of Ep.1, Ep.2 to Ep. 4, Ep. 10, and part of Ep. 11 to Ep. 12 cover the story of Vol.1 of the light novel series. The second part of Ep.1, Ep.5 to Ep.9, and part of Ep. 11 to Ep. 12 cover Vol.2 of the series.
It was announced that the VTubers Shirakami Fubuki and Natsuiro Matsuri of Hololive will have a cameo in the third episode of the anime.
The first episode aired with a runtime of ~46 minutes as opposed to the standard 24 minute long episode.
The idea of "The Detective Is Already Dead" light novel series started from a random sentence the author, Nigojû, thought of one day. The sentence was "Is there a detective on the plane?", and later became the first sentence of the story.