[5] His classmate, Hyōgo Prefectural Assemblyman Hiroshi Noma, recalled that Watase "was always reading Natsume Sōseki" and his Japanese score was always in the top 5 among 270 students.
His older brother told him to go to Keio University, but after seeing his mother in tears over the rejection letter in the garden, he decided to retake the college exams a year later.
[6] Watase then thought that after graduating, he wanted to work in a job that was demanding and cutting-edge, and his brother advised him to "take the hard path".
[9] He got a job in public relations at Dentsu but quit the company after a month to work in sales at Japark, an advertising agency in Aoyama founded by his senior.
[4] While working at Japark, an acquaintance of his brother started a real estate agency and did not have any advertising staff, so Watase would help on his days off.
[14] In 1977, while filming Hokuriku Proxy War, Watase was thrown out of an open Jeep, and his leg was crushed by the car.
[20] In 1979, Watase won the Kinema Junpo Best Actor Award for his roles in Quivering Tongue and The Baby God Gave Me.
In the Inspector Totsugawa series, which he starred in from 1992 to 2015, producer Kazukiyo Morishita recalled that Watase was "not only an actor, but a staff member", having input on the script and sometimes directing the production.
[25] In Chiri to Techin, which aired beginning in late 2007, Watase played Kusawaka Tsurezuritei, one of the four kings of rakugo in Kamigata.
[30] Director Sadao Nakajima said that Watase's interest in acting began when he met Ichirō Araki in Modern Yakuza: Three Bloody Sakura Brothers (1971).
[14] Gradually, Nakajima worried that Watase was becoming overconfident in his driving skills,[15] as in Runaway Panic Clash (1976), he was the only cast member to not use a stunt double for the climactic scene in which 200 cars and motorcycles collide.