Director Karan Johar celebrated his 40th birthday with the who's who of the film industry on May 25.  Looking elegant in a well-fitted tuxedo, Johar walked the red carpet with his mother Hiroo.  The host of the evening was close friend and designer Manish Malhotra, who had planned the entire party, including the outfits for many of the guests! Here's a look at the stars who arrived.