TolkienOnline’s original.wombat found a very interesting extract regarding Smeagol/Gollum in ROTK from Andy Serkis’ forthcoming book, Gollum: How We Made Movie Magic:
“Friday 11 April (03) was to be one of those defining moments in Gollum’s journey. I went round to Pete’s house to work on the script (ROTK) with Fran and Phillipa. It was great to see them after such a long time and we caught up on life since that mad day of ADR at Pinewood last summer. What they had in store for me, and Gollum, completely blew me away. It really brought home to me what incredibly adventurous, fearless screenwriters they were.
Fran had this idea that instead of repeating what he had established in the Two Towers – Gollum being the vicious dark side, the survivor, full of hatred and revenge, with the re-emerging Smeagol as the chink of light in his soul, the abused child, the victim who really trusts Frodo, and the side we felt pity for – that we turn it all on its head so that Smeagol was really the cold calculating passive-aggressive psychopath who play acted being the victim to get his own way. In comparison, Gollum would be less dangerous because his passion, lust and aggression were true hot-blooded emotions, flooded with feeling. The idea sent me reeling but I knew instinctively that this would be the way to go, that the character would deepen and take the audience on a very complex journey.
My only worries were, I suppose that it questioned my world-view. I had played Gollum as someone who, at the end of the day, no matter what he’d done, was a very sick addict and was redeemable because he was the victim of a powerful force that he couldn’t handle. Now we were looking at a character who is pure evil, past all redemption. My brain was frazzled by the implications.”