Co-written and first recorded by Bruce Welch (1974).
Hit version by Olivia Newton-John (US #3/MOR #1/C&W #5/CAN #1/AUS #35/NZ #7 1975).
From the wiki: “‘Please Mr. Please’ was written by Bruce Welch and John Rostill, both members of British pop singer Cliff Richard’s backing band, The Shadows (‘Apache’). Welch originally recorded the song himself in 1974 with no chart success in either the UK or US.
“In 1975, the song appeared on Newton-John’s album, Have You Never Been Mellow, and was released as the album’s second single. Newton-John’s cover of ‘Please Mr. Please’ reached the Top 10 on three major Billboard charts that year, peaking at #3 on the Hot 100 in August 1975, her fifth consecutive Top Ten hit.”
Olivia Newton-John, “Please Mr. Please” (1975):