This is the 17262nd most frequent Russian word.
сумасшедших
"Сумасшедших" means "of crazy people" or "of madmen."
The word 'сумасшедших' is used as an adjective describing people (plural and genitive case).
Он общается с группой сумасшедших людей.
He interacts with a group of crazy people.
Here again, 'сумасшедших' serves as an adjective, attributing 'crazy' to 'adventures' in the genitive plural form.
В этой книге рассказывается о приключениях сумасшедших.
This book narrates the adventures of mad people.
The term 'сумасшедших' functions as an adjective, describing 'animals' in plural and accusative case.