https://www.youtube.com/watch?v=EVDW5KfRqFk
In listening to the commercial, the singer's voice sounded familiar to me--but I was mistaken. I learned, online, that the vocalist was Beverly Kenney. I was not familiar with her name.
Ms. Kenney recorded "It's a Most Unusual Day" in 1957, accompanied by the much-admired pianist Ellis Larkins. The song appeared on her 1958 album, "Beverly Kenney Sings For Playboys."
https://www.youtube.com/watch?v=4vK_eS0sqGw
Ms. Kenney was born in New Jersey in 1932. She recorded several albums in the mid-to-late 1950s, and received critical praise for her work. She died in New York in 1960, at age 28, by suicide.
In Japan, according to Wikipedia, she "remains a cult figure."
https://en.wikipedia.org/wiki/Beverly_Kenney
As noted above, Ellis Larkins was the pianist for Ms. Kenney's "It's a Most Unusual Day"--as well as being featured on the other songs on her 1958 album (along with bassist Joe Benjamin). Mr. Larkins is perhaps best known for his work with Ella Fitzgerald--including accompanying her on the 1950 album "Ella Sings Gershwin." The album's opening song is one of the most exquisite recordings I've ever heard (a recording I've mentioned previously in this space): it is of Ms. Fitzgerald, and Mr. Larkins, performing "Someone to Watch Over Me."
Here is the 1950 recording of the song:
https://www.youtube.com/watch?v=TYEeAOTIQ2c
Here, too, is the Wikipedia page about Mr. Larkins:
https://en.wikipedia.org/wiki/Ellis_Larkins
Mr. Larkins died in 2002, at age 79. Ella Fitzgerald died in 1996, at 79.