The moment JK Rowling revealed a little more than intended

She is wizard at keeping secrets. Keeping her underwear to herself is obviously another matter.

The usually discreet JK Rowling found herself revealing a little more than she would have liked as she addressed a group of children in the US.

The writer who managed to keep Harry Potter's fate under wraps for seven books, bared her bra as she leaned forward.

Now you see it...now you don't: JK Rowling shows off her bra

Seemingly unflustered, she simply adjusted her neckline and kept talking.

Perhaps she was drawing inspiration from TV presenter Judy Finnigan, whose top fell open while on stage at the National TV awards in 2000, exposing her bra to the nation.

Blissfully unaware, she carried on talking while her image was beamed around Britain until a fellow presenter ran forward to cover her up.

Been there, done that: Judy Finnigan

Miss Rowling, 42, and estimated to have a £500million fortune thanks to her Harry Potter novels, was reading to children at the Kodak Theatre in Hollywood when her dress let her down.

Her appearance was part of her first tour of the US for seven years.