Butler had previously argued that "it's one of the darker tendencies of humanity to think everyone should fit into a mould".
The full video is expected in the next few weeks, at a time when Garfield is in the limelight. The Bafta-winning actor, 30, hosted Saturday Night Live last weekend and took part in a Spider-Man kiss spoof with Coldplay's Chris Martin.
Last month, Garfield was called out on sexism by none other than his own girlfriend, co-star Emma Stone. When asked how Spider-Man made his iconic costume, Garfield replied: "He sewed it. It's kind of a feminine thing to do but he really made a very masculine costume."
Stone was unimpressed, prompting her partner to back-track into an awkward ramble about how "we all have feminine in us".
Watch Andrew Garfield in We Exist:
- Independent