Heath Ledger’s passion for the ocean has survived his death in the form of a music video with an anti-whaling message directed by the late Australian actor.

The six-minute animated clip for the song King Rat by the US band Modest Mouse, which was released this week, features a cigar-chomping blue whale captain out hunting for humans in the sea.

The powerful, but dark, video features graphic images of a crew of whales and dolphins on board the fishing vessel catching swimming men, skinning them, processing their meat and feeding them to hungry seal pups.

Ledger, a keen surfer and anti-whale activist, came up with the concept after approaching the indie band to make a clip for their song in January, 2007.

The actor then contacted Daniel Auber, a concept designer based in Los Angeles, whom Ledger had met on the set of Terry Gilliam’s 2005 film The Brothers Grimm, to make the video.

Mr Auber told The Times the pair spent three weeks working on the the video at the offices of Gilliam’s visual effects company in Covent Garden, while Ledger was in London filming the Batman movie The Dark Knight in May, 2007.

“We had a lot of fun making this video, but obviously it is a serious video,” Mr Auber, who co-directed and illustrated the clip, told The Times.

“Heath was very interested in defending the lives of whales and dolphins and the whole problem with Japan at the moment and whale hunting. So it was very important for him to make a video that would make an impact. We needed to have the shock factor because if it wasn’t dark it wouldn’t be impressive, and if it wasn’t impressive nobody would think about what we are doing to wildlife in the ocean.”

Mr Auber said Gilliam was like an artistic father to the pair, who included an homage to Monty Python in the King Rat clip in the form of animated trumpets blasting out from the clouds. Gilliam provided self-portrait cartoons which were used as the face of the sun in the clip.

While the video was “fully conceived down to the last detail” by Ledger, it remained unfinished when he died of an accidental overdose in January, 2008. Mr Auber said a team from The Masses, a collaboration of musicians and directors that Ledger belonged to, decided to complete the work in his honour.

The clip concludes with a poignant message: “This began with our friend, a great defender of life, and was completed in his spirit.”

A statement on The Masses website said: “Heath’s vision, brave and unapologetic in its nature, would marry his love of bold and original music with his impassioned stance against the illegal commercial whale hunts taking place off the coast of Australia each year. Heath’s intention was to raise awareness of modern whaling practices through a potent visual piece without having to say a word.”

Ledger, who this year won a posthumous best supporting actor Oscar for his chilling portrayal of The Joker in The Dark Knight, was reported to have been considering a role as Captain Paul Watson, the anti-whaling campaigner who runs the Sea Shepherd Conservation Society, before he died.

All proceeds from the sale of iTunes video downloads of the song for the first month will be donated to the society.

Ledger had previously directed the video for the song Morning Yearning, by the US singer Ben Harper, who is also a member of The Masses collective.

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