The royal wedding of Prince William and Kate Middleton is only hours away — which incidentally, may also coincide with the start of a zombie invasion in downtown London.

That humorous scenario is part of the latest marketing scheme from the creators of "Class 3 Outbreak", an online Google Maps zombie simulator that pits the undead against the living in an epic battle. The special edition "Royal Wedding Map" features Kate Middleton, Prince William and their guests outside Westminster Abbey — as well as an uninvited horde of the living dead that suddenly crash the festivities.

“After extensive testing of the simulator I can attest that things don’t bode well for William and Kate,” says the site Google Maps Mania. “By my reckoning the happy couple will enjoy about five minutes of married life before joining the leagues of the walking dead.”

Anyone who watches the AMC original series, "The Walking Dead," knows that the key to preventing the undead from ruining a good time is to simply be prepared. Thankfully, Josh Harrison over at has created a handy guide, “Surviving Zombies at the Royal Wedding: A Handbook,” that includes five things to remember if you start to hear more "brainzzz" than "I dos."

"You might be tempted, after the bioengineered human strain of mad cow disease takes hold of the crowd, to save the bride and groom first," writes Harrison in one handy tip. "Resist the temptation. Don't get me wrong: I think William and Kate are stand-up people, and they will make a wonderful royal couple. In a combat situation, though, you have to keep your priorities in order."

"Her royal majesty is the single greatest threat to zombie supremacy currently breathing on planet Earth. Pay whatever cost is required to ensure that she makes it out alive."

While this all a bit of fun before the big day, you just never know what might happen. Your best bet is to simply stay home and watch the ceremony from the comfort of your home. Although with a start time of 6 a.m. here on the East Coast, if you're really awake for the nuptials, you're probably a zombie anyways.

Michael d'Estries ( @michaeldestries ) covers science, technology, art, and the beautiful, unusual corners of our incredible world.

A royal wedding zombie attack
What would happen if the living dead suddenly crashed Prince William and Kate Middleton's nuptials?