The first thing you should do is look for the original key. The key should be in the trunk beside the spare. There's a cut-out in the foam where it's stowed. If you can't find the key then listed below are some tips on removing the lugs.
1 - If you don't need to get the rims off right now, you can make an imprint of the keyed lugs using pieces of a Styrofoam coffee cup, and send it to McGard and they'll send you the correct key.
Visit McGard's website .
2 - Some people have reported good results using various tools like pipe wrenches to twist the lugs until they come off. One tool that appears to be made for that purpose is from Amazon.com .
Be aware that any of the methods listed above could result in damage to your rims or your car if not done correctly. Take proper precautions to protect you and your vehicle.
Thanks to members of the Reatta forums for this information.