From Cap’n Video’s Wikipedia

The film begins with a clip of Zavadil’s most notorious stunt in which he attempted to dive into a covered swimming pool from a ladder. The ladder was unstable and his jump resulted in a head-first landing on the concrete deck. Zavaldil then fell into the tarp of the pool, and nearly drowned as it sank until a neighbor came by and saved him. Zavadil fractured his neck as a result requiring a six-month recovery.[4][5] The news of the failed stunt received attention from various international television shows.