For decades, thousands of vulnerable migrants have been enslaved onboard untraceable Thai fishing boats lingering far out in international waters. These men are cheated into dangerous, unpaid labour, then beaten, starved and worked round the clock.

Governments are now cracking down on this brutal industry. But as the world's insatiable appetite for low-cost seafood persists, perpetrators are finding ways to navigate the restrictions.

Can those determined to stop this illicit trade succeed in overcoming the corruption of a multi-billion dollar industry?

From Series 7 of the award-winning series, Undercover Asia