It also doesn't hurt that it took place in the '30s.
The dress is a (splurge!) reproduction from Stop Staring, $170; the shoes are vintage and a steal at $23; the brooch is also from the era, $45.
Seen any good movies lately? Do you also refer to Colin Firth as Mr. Darcy even though that movie was (wait for it) a mini-series from 1995? Maybe you're a fan of the '30s and might see The King's Speech now? Do tell.