Hidden Door is an AI-powered social role-playing game studio that uses machine learning and narrative AI to transform works of fiction into interactive story experiences. Hidden Door's Twitter Score is 4.0 out of 1000 as of July 2026, ranking #208,180 among 531,432 tracked accounts.
Hidden Door was co-founded by Hilary Mason and Matt Brandwein, with Mason serving as CEO and Brandwein leading product. The platform lets players inhabit licensed and public-domain fictional worlds through collaborative narrative play, and its architecture is designed so that language models are not trained on partners' content. The studio entered early access in 2025.
Hidden Door raised a $7M seed round led by Makers Fund, with participation from Northzone, Betaworks, Brooklyn Bridge Ventures, and Homebrew. Hidden Door has published 495 posts on the platform. The account has been mentioned by 2 accounts, with 3 total mentions.
Who follows Hidden Door on X?
The accounts that follow Hidden Door include 28 founders, 7 angel investors, 2 influencers and 4 VCs, among them Marguerite, Jon Lai, Seth Goldstein, James Young, Jutta and Andy Weissman.