When harassed advertising executive Timothy Westerby hits his head on the morning of his daughter's society wedding, he awakes to find himself in the company of Polly Perkins, a 1920's Flapper girl straight out of his current advertising campaign.

It soon becomes all too clear that no-one else can see or hear her, and when another bump on the head transports Timothy back to 1926 and the Savoy Hotel,

the wedding preparations disintegrate into chaos as friends and family attempt to lead Timothy back to reality and his daughter own the aisle before the newly arrived 'In-Laws' abandon the wedding.