She was appearing alongside her fellow judges on The Voice to talk about the new series of the show.
Although because it was The One Show there were also sections on the armed-forces covenant and humpback whales.
Also this 96-year-old who works a five-day week.
Some people got mad.
Some people made funnies.
Some men also had some thoughts.
The BBC has apologised.
The corporation confirmed to BuzzFeed News this morning that 424 people have complained.
A spokesman said:
The One Show allows guests to choose their own attire and pop stars often opt for something glamorous or striking. We didn't feel that Rita's outfit would be outside of most viewers' expectations of that of a major pop star, but we appreciate that tastes vary.