The reality TV star was seen at Mischa's Secret Garden event at the Kensington Roof Gardens accompanied by two hot models - BB Kaye and Matthew Holbrook.
Although she was without her Chelsea co-stars, Rosie looked like she was having a great time hanging out with the guys and even sat sandwiched in between them while watching the catwalk show, which was hosted by Take Me Out: The Gossip's Zoe Hardman.
The trio also enjoyed a performance from singer Delilah, and BB - who has previously appeared on Channel 4's modelling competition Dirty Sexy Things - described it as "epic".
Other guests included former EastEnders actress Preeya Kalidas, X Factor contestant Kye Sones and of course, Mischa Barton herself, who was on hand to introduce her fashionable range of iPhone 5 cases.
While Rosie opted for a casual outfit, wearing bottle green jeans and a leather gilet, Mischa glammed it up in a flowing pale green dress and jewelled headpiece.
And if Rosie's model mates weren't enough eye candy for the room, Mischa enlisted some hunky models of her own to appear at the bash too!
Whose outfit do you prefer - laid back Rosie or dressed up Mischa? Let us know in the comment box below. The best comment across the website each week wins £50!
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