Born in 1966, Watanabe joined Studio Mates in 1986 and debuted his first original picture with the same studio. In 1988 he moved to Shinei Videos and was active in a wide range of roles including key animator, animation director, and director. Watanabe directed the short theatrical release Obachan no Omoide(2000), and the feature filmDoraemon: Nobita’s Dragon 2006(2006) and became a free agent in 2011. After that time, he tirelessly built up his directing portfolio with projects such as the TV series Mysterious Girlfriend X(2012), Danchi Tomoo(2012-15), If Her Flag Breaks(2014), Space Brothers(2012-14), and Ace Attorney(2016). Three TV series directed by Watanabe aired in 2018, including After the Rain, Gurazeni, and Major 2nd. Children of the Seais his fourth time directing a full-length theatrical release.