The Backwater (共喰い, Tomogui) is a 2013 Japanese drama film directed by Shinji Aoyama, starring Masaki Suda. It is based on the Akutagawa Prize-winning novel by Shinya Tanaka and adapted by Haruhiko Arai. The film won the Best Director award from the Swiss critics' federation and the Best Film award from the Junior Jury's at the 2013 Locarno International Film Festival.