Signal the Movie[a] is a 2021 Japanese police procedural thriller drama film directed by Hajime Hashimoto [ja] and co-written by Kōsuke Nishi and Hiroshi Hayashi; the film is based on a television series with a same name by Akira Uchitaka and Kosuke Suzuki, which in turn is a remake of a South Korean television series with a same name by Kim Eun-hee.
Distributed by Toho, it continues where the television series had left off, as Kento Saegura, Misaki Sakurai and Takeshi Ooyama investigate mysterious car accidents occurring in both past and present era.
Kentaro Sakaguchi, Michiko Kichise, Kazuki Kitamura, Yuichi Nakamura, Tetsuhiro Ikeda and Kaede Aono reprises their roles from the television series, with Tetta Sugimoto, Nao, Tetsushi Tanaka, Takeshi Kaga and Tsuyoshi Ihara joining the ensemble cast.
[2] The film featured a brand new story that was not present in the South Korean television series or any adaptations prior.
James Marsh from South China Morning Post gave a mixed review, stating "Existing fans of the television show will doubtless already have their tickets booked for this frantic and fitfully entertaining continuation, but curious parties approaching Signal the Movie for the first time will be better served seeking out the small screen series first – or even the superior Korean incarnation, both of which are streaming on Netflix.