The crews are eager to hit the ice and optimistic for the start of the winter fishing season, but Mother Nature has other plans; inconsistent weather leaves Trevor and his crewman Riley on thin ice.

The Ferals lose a team member in the unforgiving outback, and Shane gets an attractive offer that could break up his partnership with Russell.

Jacqui and Andrews' big gold dreams are stalled by communication issues, and the Poseidon Crew battle wet weather to unearth a monster pay day.

Truckworks clear a burnt-out B-Double, Wagga Truck Towing head to a farm to salvage a Steiger, and Clayton's Towing take on a recovery job to transport a Lockheed P3-Orion to Queensland Air Museum.

The Poseidon Crew battle challenging terrain in the mountains of High Country Victoria, and promising signs could lead the Gold Devils to a million-dollar pay day.

New recruit Sherl hopes to restore faith with his bosses on Team Cook, and Clarry's Indigenous clients dream of building a new life on their ancestral lands using proceeds from caught bulls.

Desperate to land a peak-price tuna, Adam hooks a leaping shark and an undersized fish instead. Meanwhile, Steven considers a multi-million-dollar licence that could change his future.

In the United Kingdom, engineers battle tight deadlines, complex terrain and live infrastructure to build HS2 - a record-breaking high-speed railway linking London and Birmingham.

The Mine SOS team have just six days to install a full-scale hard rock mining operation and deliver a potentially life-changing payday for hard rock rookies Nathan Malatesta and Steve Ogilvie.

Shane and Russell double down with two gold plants, the Gold Timers scale up with an eight-tonne loader, and Brent hires his 14-year-old son to drive the Poseidon Crew's 40-tonne articulated truck.

The Dust Devils pour $40,000 into a new Heap Leach plant, 50°C heat threatens to shut the Ferals down, and an angry confrontation could see Marcus, Linden and Dale thrown off of a lease.

Irv restores a golden supercar, a 1970s Lamborghini Espada, for a client in the Middle East. Hidden structural damage and spiralling engine issues threaten the entire project.

Karl fights permafrost on his cut, Ken's wife visits to discover that he is on the verge of going broke, and Big Al's excavator gets into trouble.

Shane and Russell battle freak rains, a blown circuit could destroy the Poseidon Crew's chances of a record weigh-in, and the Ferals deliver their biggest haul of the season.

A swarm of bloodsucking ticks prove no match for Jacqui and Andrew, Rob and Turbo face costly dryblower repairs, and the Poseidon Crew are hit by fierce storms that could shut them down for days.

Six weeks into the mackerel season, the Wildcard crew faces incredible highs and lows; a record haul brings triumph, but injuries, tensions, sharks and a sinking rowboat could threaten it all.

A team of treasure hunters begin their hunt for a lost fortune in gold - and make an extraordinary discovery near a dry riverbed that proves that they are on the right track.

Nika and Chris face a cash crunch. No gold forces Cam to send one of his crew home. Ken and Guillaume find a prime location to salvage their season.

It's the end of the season for two teams in Western Australia; as the McGhies battle accidents and mechanical problems, a rich source of gold may have disappeared when the Gold Devils need it most.

Jacqui and Andrew must push through hostile country with their quad bike broken to find gold, and Neville and the Poseidon Crew get to explore German Gully to search for a legacy for Nev's family.

The Desert Diggers battle to get their dry blower running, Shane and Rusty hunt for big nuggets at Fantasy Gully, and Jacqui and Andy's push to reach gold lands them in a life-or-death situation.

The countdown has ended. Gordon and his team want to process the last trailer of gold-bearing material before storms stop all work. James will soon find out if his work at 'Three Peaks' has paid off.

Dramatic phone footage reveals what it's like to get caught in a flight going up in flames and the science of how firefighters deal with aviation infernos.

While on the search for billions of dollars in gold, historian Tanya uncovers a shocking new theory that flips the hunt to the east.

The Mifsuds call on their kids for some desperately needed help, Max and Glen battle unreliable machinery, and Ray finally gets a handful of decent sapphires out of his new claim.