Little Mark and Liam's road trip to Chirk puts Little Mark in the driver's seat of a 1966 Austin-Healey, while Liam almost runs out of track testing a child's ride-on train. Big Mark is over the moon when a rare, autographed John Lennon album comes into the shop but with such a high price tag can Vicki talk her father back down to earth? When Little Mark is presented with a recovered piece of the sunken ocean-liner the Lusitania, he sends out an S.O.S. to Big Mark to keep the deal afloat.