Herbie, the Volkswagen Beetle with a mind of its own, is racing in the Monte Carlo Rally. But thieves have hidden a cache of stolen diamonds in Herbie's gas tank, and are now trying to get them back.

When a young auto salesman is forced to give up a vacation with his wife in order to drive a big American car to its new owner who lives on the Riviera, he makes the best of things. First, he gets and old friend to ride along with him. Then, the two of them are joined by another pair of men who want to ride south.