Sugababe Heidi loses her shoe on the catwalk

The hair, make-up and dresses were perfect, the steps had been rehearsed, and the celebrity audience was in place.

But you can't plan for everything. And as Heidi Range and her Sugababe bandmates marched down the catwalk last night she stepped right out of her designer shoe.

The Push The Button singer looked horrified as she realised her fashion faux pas. But, a true professional, she didn't miss a step.

Oops: Heidi's heel slips off as she and Sugababes Amelle Berrabah and Keisha Buchanan walk the catwalk at the Natural History Museum in London last night

In her one remaining shoe the 25-year-old kept up with her bandmates Keisha Buchanan and Amelle Berrabah, although by now she was a good few inches shorter.

One thing Heidi couldn't control, however, was her laughter. The audience joined in as she screamed with amusement at the mistake.

Carry on: Heidi can't control her laughter as she leaves the shoe behind on the runway

Heidi picked up the offending shoe as she headed back down the catwalk

The three bandmates, in their matching metallic pink studded dresses, were taking part in the Fashion for Relief show at the Natural History Museum in London.

The charity show, organised by Naomi Campbell, saw the A list came out in force at London Fashion Week.

If the shoe fits: The singer playfully waves it at the audience

Striding out: The Sugababe girls looked picture perfect as they set off