The plant is featured in Harry Potter in the very first book, but it completely understates the actual danger of the plant. At least based on your link, and how even touching it can be fatal.
For those wondering, it's the first potion class in book 1.
In The Prisoner of Azkaban it's mentioned that the potion is particularly complex to make, though it doesn't actually go as far as to explain the reason behind the difficulty in making it.
The plant is featured in Harry Potter in the very first book, but it completely understates the actual danger of the plant. At least based on your link, and how even touching it can be fatal.
For those wondering, it's the first potion class in book 1.