Nana and Shota are a newlywed couple and Nana is 15 years older than Shota. Nana works as a designer and Shota works as a gym trainer. They both enjoy mystery. The newlywed couple then move to an apartment and they attend a resident’s meeting there. Nana and Shota become involved in murder cases that take place at the apartment. Residents get murdered one by one. Some residents have a motive, but those suspects have an alibi. Because of this, an arrest has yet to be made.
Episode 1
Newlyweds Nana and Shota moved into a newly bought mansion where the residents decided to play an exchange killing game.
Episode 2
An exchange killing game has started right after the mansion administrator fell from the roof top and died.
Episode 3
Fujii is forced to be the next killer as the person he hates, Yamagiwa, has been killed. That’s how the game works.
Episode 4
Shini makes her boss die in an explosion of his own restaurant. In her turn to kill, she’s very scared.
Episode 5
Nana and Shota discover Misato and Goro are killed and surrounded by birthday cake in room 502.
Episode 6
Episode 7
Kayo in Room 102 was killed and only one of her feet was found in her husband, Toshiaki’s, golf bag.
Episode 8
Shota gathers 3 people and suggests 4 names who are suspected to have killed Ukita. One of the names is unexcepted.
Episode 9
Someone killed Kono for Nana. Is this really an exchange killing game? Shota has found a clue that may reveal the truth.
Episode 10
Shota is locked up in room 402, with a mystery boy. Nana thinks Shota’s missing because he has found the proof.
Episode 11
Sanae is arrested for assaulting Nana. Shota goes to find the new resident in room 304 to help check on Nana’s computer.
Episode 12
Shota enters Kinoshita’s room where lots of data referring to the case are dispersed and finds some suspicious evidence.
Episode 13
Shini lets Kuon to escape from the police as they may be arrested for attacking Shota and suspicion of killing Hakamada.
Episode 14
Shota shouts out 6 names whose finger prints are found on a paper that has Yoko’s name on it to see their reactions.
Episode 15
Shota, Nikaidou and Minami protect Sora and capture Soichi and deliver him to the police. Sora then reunites with Sumika.
Episode 16
Kamiya is brutally killed. His heel cord is cut and his whole body is screwed and smiling like other victims.
Episode 17
Episode 18
Minami attacks Tamiya and asks if he killed a young girl in Kochi five years ago. Nikaido has been missing for two days.
Episode 19
Nikaido’s AI program shows Kuroshima is most likely the suspect behind all the events but he makes excuses for her.
Episode 20
Shota wakes up and finds that his and Kuroshima’s hands and feet are tied and they are being put on a poisonous drip.
