No lie, the bitcoin white paper.

Reading it made me realize that this wasn't just some marketing scam or hype, and that there was real engineering, game theory, and cypherpunk ethos behind it.

After that, it was probably aantonop's Mastering Bitcoin which helped me understand the underlying technicals a little better, though i'm still by no means an expert

First, they told me about the problem (Fiat Money) and then they showed me the solution (BTC). After watching videos and reading a few things about how inflation, the government, and elites are taking my money without me even realizing it... Understanding Bitcoin and fearlessly diving into the rabbit hole was almost a no-brainer.

For me it was this documentary by ARTE It's in french and was deleted by youtube https://hongbaob.tc/satoshi

It was this article!

Changed my life and made me change my mind about money and bitcoin