Katy Perry performs on stage as part of Witness: The Tour, at Ziggo Dome, on May 26 in Amsterdam, Netherlands.
Katy Perry performs onstage during her "Witness: The Tour" tour opener at Bell Centre on September 19, 2017 in Montreal, Canada.
Singer/songwriter Katy Perry performs with dancers during a stop of Witness: The Tour at T-Mobile Arena on January 20, 2018 in Las Vegas, Nevada.
Katy Perry performs onstage during her "Witness: The Tour" tour opener at Bell Centre on September 19, 2017 in Montreal, Canada.
Katy Perry performs on stage as part of Witness: The Tour, at Ziggo Dome, on May 26 in Amsterdam, Netherlands.
Singer-songwriter Katy Perry performs live in concert on her 'Witness' The Tour event held at the AT&T Center on January 10, 2018 in San Antonio,...
Katy Perry performs on stage during her Witness Tour at Birmingham Arena on June 18, 2018 in Birmingham, England.
Singer-songwriter Katy Perry performs in concert during 'Witness: The Tour' at the AT&T Center on January 10, 2018 in San Antonio, Texas.
Singer/songwriter Katy Perry performs during a stop of Witness: The Tour at T-Mobile Arena on January 20, 2018 in Las Vegas, Nevada.
Singer/songwriter Katy Perry performs during a stop of Witness: The Tour at T-Mobile Arena on January 20, 2018 in Las Vegas, Nevada.
Katy Perry performs live on stage during the 'Witness: The Tour' at The O2 Arena on June 14, 2018 in London, England.
Singer/songwriter Katy Perry performs with dancers during a stop of Witness: The Tour at T-Mobile Arena on January 20, 2018 in Las Vegas, Nevada.
Katy Perry performs onstage during her "Witness: The Tour" tour opener at Bell Centre on September 19, 2017 in Montreal, Canada.
Katy Perry performs on stage as part of Witness: The Tour, at Ziggo Dome, on May 26 in Amsterdam, Netherlands.
Katy Perry performs on stage during her Witness Tour at Birmingham Arena on June 18, 2018 in Birmingham, England.
Katy Perry performs in concert during her "WITNESS: THE TOUR" tour at the Ericsson Globe Arena on June 10, 2018 in Stockholm, Sweden.
Katy Perry performs in concert during her "WITNESS: THE TOUR" tour at the Ericsson Globe Arena on June 10, 2018 in Stockholm, Sweden.
Katy Perry performs during her "Witness" tour at SAP Center on November 14, 2017 in San Jose, California.
Singer/songwriter Katy Perry performs with dancers during a stop of Witness: The Tour at T-Mobile Arena on January 20, 2018 in Las Vegas, Nevada.
Singer-songwriter Katy Perry performs live in concert on her 'Witness' The Tour event held at the AT&T Center on January 10, 2018 in San Antonio,...
Katy Perry performs onstage during her 'Witness: The Tour' at Little Caesars Arena on December 6, 2017 in Detroit, Michigan.
Katy Perry performs onstage during her "Witness: The Tour" at Madison Square Garden on October 6, 2017 in New York City.
Katy Perry performs onstage during her "Witness: The Tour" at Madison Square Garden on October 6, 2017 in New York City.
Katy Perry performs onstage during her "Witness: The Tour" tour opener at Bell Centre on September 19, 2017 in Montreal, Canada.
Noah Cyrus performs onstage during Katy Perry's "Witness: The Tour" tour opener at Bell Centre on September 19, 2017 in Montreal, Canada.
Noah Cyrus performs onstage during Katy Perry's "Witness: The Tour" tour opener at Bell Centre on September 19, 2017 in Montreal, Canada.
Noah Cyrus performs onstage during Katy Perry's "Witness: The Tour" tour opener at Bell Centre on September 19, 2017 in Montreal, Canada.
Noah Cyrus performs onstage during Katy Perry's "Witness: The Tour" tour opener at Bell Centre on September 19, 2017 in Montreal, Canada.
Noah Cyrus performs onstage during Katy Perry's "Witness: The Tour" tour opener at Bell Centre on September 19, 2017 in Montreal, Canada.
Katy Perry performs during her Witness world tour at SAP Pavilion in San Jose, Calif., Tuesday, November 14, 2017.
Katy Perry performs on stage during her Witness Tour at Birmingham Arena on June 18, 2018 in Birmingham, England.
June 2018, Germany, Berlin: US American singer Katy Perry performs at the Mercedes-Benz Arena during her "Witness" Tour. Photo: Britta Pedersen/dpa
Katy Perry performs live on stage during the 'Witness: The Tour' at The O2 Arena on June 14, 2018 in London, England.
Katy Perry performs in concert during her "WITNESS: THE TOUR" tour at the Ericsson Globe Arena on June 10, 2018 in Stockholm, Sweden.
Singer/songwriter Katy Perry performs during a stop of Witness: The Tour at T-Mobile Arena on January 20, 2018 in Las Vegas, Nevada.
Fans pose for photos before a performance by singer/songwriter Katy Perry during a stop of Witness: The Tour at T-Mobile Arena on January 20, 2018 in...
An image of an eye is projected on a screen before a performance by singer/songwriter Katy Perry during a stop of Witness: The Tour at T-Mobile Arena...
Singer/songwriter Katy Perry performs during a stop of Witness: The Tour at T-Mobile Arena on January 20, 2018 in Las Vegas, Nevada.
Katy Perry performs onstage during 'Witness: The Tour' at Madison Square Garden on October 6, 2017 in New York City.
Miley Cyrus and Noah Cyrus perform onstage during Katy Perry "Witness: The Tour" at Madison Square Garden on October 6, 2017 in New York City.
Katy Perry performs on stage as part of Witness: The Tour, at Ziggo Dome, on May 26 in Amsterdam, Netherlands.
Katy Perry performs on stage as part of Witness: The Tour, at Ziggo Dome, on May 26 in Amsterdam, Netherlands.
Katy Perry performs on stage as part of Witness: The Tour, at Ziggo Dome, on May 26 in Amsterdam, Netherlands.
Katy Perry performs on stage as part of Witness: The Tour, at Ziggo Dome, on May 26 in Amsterdam, Netherlands.
Katy Perry performs on stage as part of Witness: The Tour, at Ziggo Dome, on May 26 in Amsterdam, Netherlands.
Katy Perry performs on stage as part of Witness: The Tour, at Ziggo Dome, on May 26 in Amsterdam, Netherlands.
Katy Perry performs on stage as part of Witness: The Tour, at Ziggo Dome, on May 26 in Amsterdam, Netherlands.