Sea Shepherd is ramping up its campaign against a controversial shark-kill policy with a new documentary.

The documentary, called Apex Harmony 'The Shark Cull', features the mother of a man killed by a great white shark, as well as graphic images of dead sharks on the ocean floor.

But Sea Shepherd has been criticised for exposing the contractor employed by the West Australian government to catch and kill sharks earlier this year.

The documentary named the man who it claimed was paid more than $600,000 for catching and killing sharks off the south-west coast of Western Australia for three months during the state government's trial.

The WA government trialed a catch-and-kill program targeting great white, bull and tiger sharks larger than three metres, after seven people were killed over three years.

Despite large protests, the government hopes to run the program again for three years starting in November, but is waiting on federal environmental approval.

Sea Shepherd said it hoped the documentary would expose what it said is the cruel treatment of sharks.

"We need these apex predators in our oceans," Sea Shepherd director Jeff Hansen said.

"In order for us to live on this planet, we need to live in harmony with them because we need them, we need healthy oceans.

"We're not disconnected from nature."

A state government spokesperson said opponents of the policy ignored the millions of dollars the government is spending on non-lethal research and shark monitoring.

Apex Harmony 'The Shark Cull' will be shown in select cinemas, Australia-wide, from August 26-31.