Mike falls for an ultra-rare 1935 Auburn convertible and makes a promise to the married couple who own it; months later, Mike takes the convertible on an epic Route 66 road trip to honor his promise, but it may not reach its destination.

If the guys can't get a mammoth 1929 Roadster safely down a decaying 100-year-old elevator they will be $20,000 in the hole. Plus, Mike uncovers a surprise when he hears hissing coming from beneath an out-of-control collection.