Denise Richards lunch Beverly Hills

Who knew these two were pals?!

Denise Richards and Joanna Krupa lunched and shopped together Thursday afternoon in Beverly Hills stopping by Villa Blanca for eats and vintage luxury retailer LXRCO afterware for some "gently used" goods.

Krupa wore a sexy maxi-dress that showed off a whole buncha skin, while Denise kept things under wraps in a brown leather biker jacket and pants.

All the photographers were hot and bothered by these two hotties and ended up tripping over each other just to get pictures ... check out the video below AND click through to find out what Joanna says about Justin Bieber ...