He and co-host Holly Willoughby discussed the film – which was released last Friday – with commentators Julia Hartley-Brewer and Matthew Wright.
Bringing Netflix royal drama series The Crown into the debate too, the group explored the way the late Princess of Wales is portrayed in cinema and television.
Phillip told them he’d been to the pictures over the weekend, where he watched “bizarre film” Spencer.
It wasn’t all bad though, as the presenter claimed he felt the movie was “beautifully shot” and showcased “amazing acting”.
However, he added: “I don’t see that there’s any truth in this whatsoever. It’s just like this mad fabrication”.
Referring to one of director Larrain and screenwriter Steven Wright’s creative choices, Phillips argued: “It paints her as being a total nutcase who talks to Anne Boleyn”.
Spencer was received incredibly well when it first screened at Venice International Film Festival back in September.
But it seems Mr Schofield is convinced the critics have made a huge error with all their four and five-star reviews.
Speaking of Diana’s sons, Princes William and Harry, he explained: "All I could think of throughout all of this, is those poor boys”.
Julia agreed that it must be hard for William and Harry to see their mum’s private life detailed on screen over and over.
She remarked: “It’s horrible. I can’t imagine what it must be like for them every single day with people constantly talking about their late mother”.
But the journalist and radio presenter added that this doesn’t mean it’s ok to dictate the way film-makers handle their subject matter.
She went on to say: “I have to say, I think it’s ridiculous this idea that friends of or family members of Diana or the boys should be able to dictate how a TV series made by Netflix should treat their mother.
“I think that’s quite outrageous, I mean, they should have artistic freedom”.
“The only problem is”, Julia concluded, “there’s a lot of people, certainly in America, that think that it’s all like a work of fact, not a work of fiction”.
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