Create an educational series teaching all the chemistry, lab techniques (for small batches), and chemical engineering (for large batches) to create chemical weapons (sarin, VX, etc.). On one hand hand, people will be interested in it (so able to generate revenue through monetization e.g., ads) -- it is novel and conventionally-believed-to-be forbidden knowledge. On the other hand, there will likely be strong efforts to censor it, which will provide its own publicity by the Streisand effect.
A defense might be that the science and engineering covered are applicable much more broadly than chemical weapons.
Add some biology education by replicating the experiments by which the chemicals were discovered.
I suspect the main reason such a series does not exist already is because chemical weapons production is inherently extremely dangerous, so no one wants to do it just for entertainment. (How does the danger compare to other things people do for money in entertainment? Football?) Work around this danger problem by substituting chemicals and reactions which are similar (perhaps visually) but much safer. There is considerable preparatory work necessary to discover these safer substitutes, including the seeming chicken-and-egg problem of knowing what the real thing looks and behaves like in order to mimic it accurately.
The series might be able to build on responses of (foolhardy) people who do it for real after watching and discover inaccuracies: the inaccuracies can be corrected over time.
It might also need to cover how to make the equipment and tools that are difficult to obtain. This will be very expensive to produce, though perhaps not very expensive compared to other big-budget entertainment.
What other forbidden knowledge education might sell well as edutainment?
Making nuclear weapons would cover enriching uranium with gas centrifuges, or making plutonium in a reactor, including making these equipment. I suspect the first is military secret and the other is trade secret.
Weaponizing anthrax seems feasible: the raw material is a common soil bacterium. The process is probably also secret.
Making illegal drugs, a la Breaking Bad.
Inspired by Youtube videos of lockpicking and lock snapping, which I feel have done far more good (as education) than harm.