The actor, who played the character for more than a decade - appearing in three 'Lord of the Rings' films and prequel 'The Hobbit', which has also been split into a trilogy shot the scenes last week in New Zealand.
Last year, Mckellen opened up about his battle with prostate cancer, reported Showbizspy. "You do gulp when you hear the news. It's like when you go for an HIV test, you go 'arghhh is this the end of the road?' They say you have cancer of the prostate and then that you can have it zapped.
You can have it snipped but you are not a candidate for that. You are waitful watching," he said. The actor revealed he is yet to receive any treatment for prostate cancer and insists it is "no big deal". "I've had it for six or seven years, when you have got it you monitor it and you have to be careful it doesn't spread.
But if it is contained in the prostate it's no big deal. "Many, many men die from it but it's one of the cancers that is totally treatable so I have waitful watching. I am examined regularly and it's just contained, it's not spreading. I've not had any treatment."