"Temporary Secretary" was released as a third single from the album only in a form of 12" single, along with the ten-minute "Secret Friend" as its b-side, limited to 25000 copies and therefore failed to chart. A 7" single exists only as a demo for radio stations. It exemplifies both the whimsical nature of the album and McCartney's use of synthesizers and other electronics in the creation of the album. McCartney claims that he viewed the song as an "experiment."
Music website Allmusic.com said of the album, McCartney II:
In retrospect, the record is muddled and confused, nowhere more so than on the frazzled sequencing of "Temporary Secretary," where McCartney spits out ridiculous lyrics with a self-consciously atonal melody over gurgling synths. Things rarely get worse than that....
In contrast, music website popmatters.com said, in reviewing the 2011 reissue of McCartney II:
“Temporary Secretary” is a manic, futuristic laser blast with an actual melody simmering underneath. It would be pointless to compare it to anything McCartney had ever done before, and would be equally so to compare it to anyone else as it couldn’t possibly be anyone else. More than any other song on either eponymous album, “Temporary Secretary” illustrates the complex nature of Paul McCartney’s musical output...
In 2013, Rolling Stone Magazine rated "Temporary Secretary" the #36 all-time Paul McCartney post-Beatles song, calling it a "cult favorite" and an "oddly catchy electro-pop nugget, about a slightly creepy-sounding guy looking to hire a temp."