Maybe Bruno Mars’ next concert will be “Somewhere in Brooklyn.”

One week before Bruno Mars brings his “24K Magic” tour to Madison Square Garden for a two-night stay this month, the singer will take to the stage at an undisclosed location for a surprise NYC concert.

Tickets for the Sept. 10 show — which is 18-plus only — are available at brunomars.com/secretshowtickets. Fans just have to fill out a form to be eligible to win two free tickets. Entry is first-come, first-served and winners will be notified via email.

The “That’s What I Like” singer’s Sept. 22 and Sept. 23 concert tickets at MSG are available for purchase on Ticketmaster for a minimum of $250 a pop, with floor seats nearing $2,000. Climbing prices — due in part to popularity and resale sites — have fans jumping on the chance to see Bruno Mars in what one can hope is a more intimate “secret” setting.

“Wanted to see you for so long and I never get tickets cause they sell out and I can’t afford to pay the outrageous prices people charge on the ticket sites! I hope I get this chance,” a fan wrote on Mars’ Facebook page.

“Entered! I can never afford tickets because of the people who re sell tickets,” another said.

Bruno Mars has been on tour since March, and still has dozens shows scheduled until he hangs up the mic this winter. He’ll return to the city next month for a one-night Barclays Center show on Oct. 4.