Fiona gets lost on Harris and Murray is all at sea when the presenters two go head-to-head in an intriguing challenge. Murray has come up with a test to find out if a more ancient form of transport could be a faster way to get around the Western Isles than a super-fast boy racer's car. Louise tops up her racing skills with one of Knockhill's top instructors and gets the chance to live her dream behind the wheel of a Formula One car. How does she perform in the wet? Calum Iain has never been happier as he puts the brand new top-of-the-range Jaguar XJ Supercharged V8 Supersport through its paces. He also discovers levels of comfort previously unknown to him in a Mark 2 Escort. And we welcome Wacky Races - a brand-new feature in which our presenters battle it out on the race track, competing against each other in a driving challenge with a twist.