Andy Serkis has likened Gollum to an addict.

'The Hobbit' actor - who reprises his role as the cave-dwelling creature in the 'Lord Of The Rings' prequel - took inspiration for his character from modern-day addiction sufferers in order to better portray possessed hobbit Smeagol battling with his power-hungry alter-ego Gollum.

He enthused: ''As an actor, you're always under the microscope and so with Gollum/Smeagol it was an opportunity to run riot. One of the great things about the character is he is very complicated, you feel sorry for him, you feel pitiful - yet you hate him.

''Smeagol has a weak personality by definition. He wasn't able to cope with the Ring of Power. It was important to find something very real that it could mean to you in this day and age. Gollum is entirely based on the notion of addiction and the way that the ring possessed him, makes his craven, lustful, depletes him physically, psychologically and mentally.''

The British star, 48, thought long and hard before coming up with his character's distinctive raspy voice and mannerisms and confessed he based Gollum's violent spasms - filmed using motion capture technology - on a cat coughing up furballs.

Andy added to BANG Showbiz at 'The Hobbit: An Unexpected Journey' press conference in London's Claridge's hotel: ''Gollum is called Gollum because of the way he sounds, writes Tolkien, and the voice had to be bound up with that. I wanted something to do with his psychology and where he would carry that pain was in his throat.

''I needed to find some action that would spark off the physicality and the voice working together, and for me it was a cat coughing up furballs!''