Rather like all those supporting actors on the original "Star Trek" such as George Takei (Sulu) and the late James Doohan (Scotty), singer Shigeru Matsuzaki（松崎しげる）will probably end his days always being known for just that one song despite having released 44 singles to date since his debut in 1970. That would be the heart-on-your-sleeve ballad "Ai no Memory"（愛のメモリー）from 1977. Plus there is that perpetual tan of his and his appearances on all of those variety programs and commercials (in voice as well as in person).
However, Matsuzaki has also done his fair share of acting over the decades including this zany detective show on TBS from 1979-1982 called "Uwasa no Keiji Tomi to Matsu"（噂の刑事トミーとマツ...The Famous Detectives Tomi and Matsu）. From what little I've seen of the show, the singer played the somewhat grumpy Detective Susumu Matsuyama who has to partner up with the faint-hearted Officer Tomio Okano to take care of cases that improbably get solved despite all of the comical stumbles that the team experiences.
The ending theme of the show turned out to be Matsuzaki's 21st single from September 1979, "WONDERFUL MOMENT" which is also a love song of sorts. However unlike the heartrending "Ai no Memory" with its touch of Latin, this ballad is as mellow and tropical as a trip down to Margueritaville. Perhaps it is where Matsuzaki's tec wanted to flee to after every case with his dopey partner. The singer's crooning style in this case reminds me of rocker Eiichi Yazawa（矢沢永吉）when he is at his most tenderhearted.
Yoshiko Miura（三浦徳子）, who took care of a lot of those early Seiko Matsuda（松田聖子）tunes among her huge list of creations, wrote the lyrics while Juichi Sase（佐瀬寿一）composed the song. Sase, incidentally, was the same composer behind the hugely successful and legendary Oricon hit, "Oyoge! Taiyaki-kun"（およげ！たいやきくん）a few years earlier.
The above link heads to the ending credits for "Uwasa no Keiji Tomi to Matsu" which succinctly shows what the show is all about.