On June 6, 1971 John and Yoko joined Zappa and The Mothers on The Fillmore East stage for a guest appearance at the end of the concert.
First they performed an Olympics cover called "Well". (The Young Rascals took The LA band's 1965 tune "Good Lovin' to Number one; NRBQ recorded their "Same Old Thing" for Yankee Stadium ).
The rest of the songs were jams, including one called "Scumbag".
Yoko, as usual, is very present.
Zappa gave Lennon tapes of the show. John and Yoko included the concert as a bonus on their 1972 double album Some Time In New York City. For a variety of reason, this did not sit well with Zappa.
The way Phil Spector mixed the tapes was dishonest. (Flo & Eddie vocals both left out of the mix; cheers and applause edited in)
But what truly pissed Zappa off is that John and Yoko took full songwriting credit for "Jamrag", which included elements of Zappa's "King Kong" from the Uncle Meat album.
Years later, Zappa would still be grinding his teeth about that move:
Today Some Time is an interesting time capsule. John and Yoko at their most political. Not always at their most musical.
Upon its release Milwaukee Sentinel music writer Stuart Wilk wrote "John, Yoko and The Plastic Ono Band have produced another shrill, superficial look at trendy leftist politics and have plunged even further into their endless echo chamber."
By the way: How many Turtles were on the stage that night?
The answer is three:
Flo (Mark Volman), Eddie (Howard Kaylan) and bass player Jim Pons.