That's Catch 22 is a novella within the Digital Devil Saga series.
Written by Tadashi Satomi, it was published in MediaWorks' Digital Devil Saga: Avatar Tuner ~The Master Guide I~ and Digital Devil Saga: Avatar Tuner ~The Master Guide II~ as two separate parts.
The novella is set in 2014 America and focuses on Heat O'Brien meeting Serph Sheffield during the murder investigation of his professor, Henry Harris.
- Heat O'Brien - A second-year student, having skipped a grade, in 's school of medicine. He is described as being eighteen years old with blond hair. Bearing a grudge against God after having lost his sister to at a young age, he is interested in medical science and genetics.
- Serph Sheffield - A second-year student at the same university as Heat. He is the youngest in his academic year at sixteen and basks in the attention it garners him. He knows a lot about the students and faculty of the school. He aids Heat in searching for the answers behind Henry's death.
- Henry Harris (ヘンリー・ハリス) - A professor of genetics at Yale. He is forty-eight years old.
- Allen Harvey (アレン・ハーヴェイ) - An FBI investigator.
- Margot Cuvier - A woman from the World Health Organization who discovers the Cuvier Syndrome, complications caused by the crystallization of somatic cells. She lectures at Yale.
|Characters (Atma Avatars)|
|Playable||Serph (Varna) - Heat (Agni) - Argilla (Prithivi) - Gale (Vayu) - Cielo (Dyaus)|
|Non-Playable||Sera - Angel (Harihara) - Harley (Hayagriva) - Jinana (Usas) - Bat (Camazotz) - Mick the Slug (Rahu) - Lupa (Cerberus) - Varin Omega (Ravana) - Twinklebell - Schrödinger - Demi-fiend|
|Junkyard||Ground Zero - Muladhara - Svadhisthana - Manipura - Anahata - Coordinate 136 - Deserted Ship - Embryon Base 2 - Vishuddha - Ajna - Karma Temple - Samsara Tunnels|
|Songs||"Pray" - "Danger"|
|Terminology||Atma - Embryon - Field hunt - Nirvana - Turn Press - Magnetite|
|Lists||Demons - Bosses - Mantra - Skills (Combos) - Items|
|Games||A's TEST Server|
|Publications||Quantum Devil Saga: Avatar Tuner - That's Catch 22 - DOGDAYS - Shinen no Matou|