Pop band Scissor Sisters are to play a special free concert outside the former prison at the Tower of London.

The I Don't Feel Like Dancin' hitmakers are heading to the U.K. for a performance as part of the BT River Of Music event for the London 2012 Festival.

And they've announced their show will be held at the Tower of London, a famous castle used to imprison treasonists prior to their execution in the 16th and 17th centuries.

In a statement on their Facebook.com page, the band writes, "Your Scissters are playing a VERY special show at the Tower Of London as part of BT River Of Music for the London 2012 Festival! We headline the Americas stage alongside a host of wonderful and diverse acts.

"Tickets to this show are FREE (subject to a booking fee) and first come first served. But, as I'm sure some of you are aware, we have to play the show of our lives at the Tower otherwise it will be off with our heads..."