U2 were about to begin recording The Joshua Tree when Amnesty International asked them to put together a tour to celebrate the organization's 25th anniversary. "It couldn't have been worse timing," said the Edge. "I was worried that all the focus and concentration would be lost. At the same time there was no way we could not do it. It seemed too important."
The group pushed back the their recording sessions and began lobbying huge stars to join the tour. "We rang everyone we knew," said Bono. "Paul McCartney, Mick Jagger, Prince. Prince was at the height of his popularity and his manager said, 'Well, just ring this number between seven and eight.' I said, 'Oh, great, is that his home number?' He said, 'No, it's the studio.' 'Will somebody pick up?' I asked. He said, 'Well, we don't know, but sometimes he walks past between seven and eight.'"
Bono was unable to land McCartney, Jagger or Prince, but Peter Gabriel, Joan Baez, Lou Reed and Sting and the Nevill Brothers were happy to sign on. It was a six-show tour in June of 1986, and for the final three nights Sting agreed to reunite the Police. They hadn't performed together since the end of the Synchronicity tour in early 1984, and had essentially broken up. Their presence on the bill guaranteed sell-outs, especially when the tour hit stadiums.
The tour wrapped up at Giants Stadium on June 15th, 1986. The Police closed out the night. They ended their set with "Invisible Sun," bringing out Bono to sing the final verse. When they finished, they handed U2 their instruments for the all-star finale of "I Shall Be Released." "It was very emotional for them," said Bono. "I think it was clear in Sting's eyes that he was not going to be in a band anymore. They had come together for this tour and that was it. It was a very big moment, like passing a torch."
The Police briefly attempted to take the momentum from the tour into the studio, but Stewart Copeland fell off his horse while playing polo the night before the session. He broke his collarbone and was unable to play drums. The group went ahead anyway, re-recording "De Do Do Do, De Da Da Da" and "Don't Stand So Close to Me" with a drum machine. This caused a terrible fight between Copeland and Sting, marking the end of the Police as any sort of ongoing creative unit. They did reunite for Sting's wedding in 1992, their Rock and Roll Hall of Fame induction in 2003 and a world tour in 2007/'08.