Investigators go on the trail of a fare dodger they suspect has avoided paying for more than 600 journeys and officers monitor Hounslow trains, a hot spot for fare evasion.

The hunt is on in Surrey for a suspect thought to have evaded close to £20,000 of fares in one of South Western Railway's biggest ever fraud cases. Revenue Protection officers Michelle and Lucky expose short farers at Vauxhall. And at London Waterloo, Jack and Jack face up to an explosive passenger, while Harry has a run in with a barrier basher

Investigators Rich and Greg go on the look-out for a fare dodger thought to be scamming Transport for London for over a year, racking up more than £5,000 in unpaid fares. At Waterloo, South Western Railway revenue protection officer Sam faces a tense situation with a man caught without a valid ticket who is more focused on finding a toilet than co-operating

Revenue Protection officer Sam from South Western is verbally abused on a train to Feltham when a man without a ticket insists on confronting her throughout his journey.

At Vauxhall station, one the capital's fare-dodging ultra-hot spots, a team of six revenue protection officers from South Western Railway set a trap to block rush hour fare dodgers and their first catch is an unrepentant man who has pushed through the barrier determined not to pay. Sam and Harry go undercover on a major sting operation at Byfleet and Haw, one of the busiest fare dodging stations outside London. And on the south coast, Lauren and Dan face threats of violence from an angry and potentially dangerous passenger who refuses to pay for his travel.

Transport for London investigators Rich and Greg are on the trail of a man they believe has run up more than £1500 in unpaid fares in east London on the Elizabeth Line. At Waterloo, South Western Railway revenue protection officers Ty and Jack chase a barrier jumper, while Sharon and Carlos set up enhanced checks on the barriers at Weymouth after multiple reports of disorder and chronic fare evasion

At Clapham there's a major operation to clamp down on fare evasion. Nathan and Dan tackle an epidemic of ticketless travel between unstaffed stations.

In Ilford undercover Investigators try to catch a suspected fare dodger they believe has racked up over £3000 in unpaid fares on nearly 500 journeys, misusing contactless.

At Vauxhall, revenue protection officers from South Western Railway are involved in a major sting operation which prompts an investigation into fraud going back seven months. A lady is stopped using a half-price ticket bought with a Job Centre Plus discount card which she doesn't have. At Southampton, Spencer is on high alert after claims that two young women who push through the barriers are being abusive and are trying to travel for free. At Waterloo Harry takes on tailgaters and the abuse of half-price child tickets at half term. And two newly trained recruits are on the Weymouth to London line - a route notorious for fare dodgers.

Investigators trail a man they believe has racked up nearly £2,500 in unpaid fares by fraudulently making contactless payments with his bank card.