Sure, you could make things easy on your guests by calling for casual evening attire. But, come on -- it's a red carpet event! Why not challenge everyone to dress to the nines and orchestrate an event they'll remember for years?
There are two ways to approach this: You can make it a black tie event, with men expected to arrive in tuxedos and women in gowns. If you think your guests won't have tuxes and gowns at the ready, you might suggest a few costume or vintage stores where they can find affordable options. Alternatively, you can ask guests to come dressed as their favorite movie actors and actresses. The latter can make for a fun guessing game and encourage guests to mingle.