The stars were out in force last night at amfAR's annual gala in Cannes - and the lady turning the most heads was none other than Katy Perry, thanks to her homage to the 'red dress' emoji. This dress obviously isn't a graphic, rather it's Marchesa, with Harry Winston jewelry and Giuseppe Zanotti heels. 

Others opting for searing hues on the night included Uma Thurman in Schiaparelli Haute Couture, and Heidi Klum in a plunging yellow number (again, with Zanotti heels)

Black was also popular among the models present, with Jourdan Dunne (DSquared2), Karlie Kloss (Marchesa), Bella Hadid and Alessandra Ambrosio (Redemption) all embracing the LBD.

Kirsten Dunst also went with black, but in a rather more sedate form...

 

Metallics were also prevalent, thanks to Milla Jovovich, Paris Hilton (she's still knocking around), and Rosie Huntington-Whitely (Galvan).

And, finally, those standing out by themselves and looking only bleedin' fabulous in the process were Elle Fanning and Dame Helen Mirren (Temperley London).