Keith Richards is inviting fans to hear select tracks from his new Crosseyed Heart album ahead of its release — but they'll have to work for it.

ABC News Radio reports that starting this week, a series of four temporary plaques will be unveiled in London or Southwest England, each one "celebrating a site of significance to the Rolling Stones guitarist's life." The location of every plaque will be shared on Richards' Facebook and Twitter accounts.

Every plaque bears a unique password, and once that password is submitted to the Crosseyed Heart website, a new song from the album will be made available. According to the report, enterprising Richards fans have already unlocked the first track, "Amnesia" (available at the Crosseyed site), by finding the password on the plaque located at his old house on Spielman Road in the Dartford section of London. The location of the next plaque will be announced Aug. 24.

Crosseyed Heart, due Sept. 18, ends a long solo hiatus stretching back to Richards' last solo studio effort, 1992's Main Offender. He was joined for the sessions by a number of past collaborators, including drummer Steve Jordan and guitarist Waddy Wachtel; also along for the ride were keyboard player Ivan Neville and longtime Stones backing vocalist Bernard Fowler.

"I had a ball making this new record and working with Steve Jordan and Waddy Wachtel again. There’s nothing like walking into a studio and having absolutely no idea what you’re going to come out with on the other end," said Richards after the debut of the record's lead-off single, "Trouble." "If you’re looking for ‘Trouble,’ you’ve come to the right place."

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