Bill Martin's "The Door Into Summer" is one of many standout tracks on The Monkees' fourth album, Pisces, Aquarius, Capricorn & Jones Ltd. "The title came from the Robert Heinlein book The Door Into Summer, which was about time travel," Martin told Monkees archivist Andrew Sandoval in the liner notes of the 1991 Listen to the Band box set. "The song is about the search for happiness, and is basically an anti-war song." Bill Martin also discussed the unique circumstances surrounding the recording of the song: "Micky tried singing it, and Mike tried it a couple of times also. They didn't like the echo at RCA, so they strung a mike from Studio A to the men's bathroom. Mike did his vocal in there to achieve the right effect."
The photo above was published in the Spring 2017 issue of Carmel Magazine and was denoted as being from Michael's personal collection. It seemingly shows Nez recording the vocal for "The Door Into Summer" in the men's room as Martin had recollected. (Michael's appearance also seems to match the August/September/October 1967 time frame in which the song was recorded.) However, in speaking with Andrew Sandoval about the story behind the photo, he neither confirmed nor rejected the idea that it was taken during the "Door" session, saying it was from Michael's archive and that he was unable to officially confirm its veracity.
An alternate mono mix of the song was made available on the 2007 deluxe edition of the Pisces album, which some believe features the men's room vocal take: