Millie Mackintosh chose a very daring dress for the Zoolander 2 premiere last night.

The fitness fanatic donned the red carpet in a black low-cut dress, which left very little to the imagination – especially when she made a few little slip-ups.

Millie revealed a serious amount of side-boob (which is nothing new on a red carpet) but what we think she didn't account for was flashing her nipple tape, too. 

The 26-year-old certainly wasn't shy about it though, as she kept on striking poses in her floor-length gown, with a split right up to the upper thigh.

And, while she was fixing her thigh-split gown, Millie made another blunder by flashing her bum. 

She lifted up the dress so high that the paps got a glimpse of her derriere and black underwear. Ooops!