Unnamed Crew Members
- A large man with a cat-eared mask, a white scarf and tiger-like arms.
- Two young women wearing cat masks and tails.
Given that the crew was led by someone who was once among the strongest members of CP9 and then became one of the top officers of the Emperor-led Beasts Pirates, it can be assumed that the Who's-Who Pirates were formidable. However, nothing is known about their overall strength in detail.
In the past, the crew was founded by Who's-Who after he escaped from prison, but at some point he was recruited by Kaidou into the Beasts Pirates. It is unclear what happened to the whole crew afterward, but some of its members still follow Who's-Who in the Beasts Pirates as a band of subordinates called "CAT'S".
- The Who's-Who Pirates are the second pirate crew to follow a cat theme; the first was the Black Cat Pirates.
- Vivre Card - One Piece Visual Dictionary (Card #1552), Information about Who's-Who is revealed.
- One Piece Manga and Anime — Vol. 97 Chapter 979 (p. 12) and Episode 985, Who's-Who is stated by King to have formerly been captain of his own crew.
- One Piece Manga and Anime — Vol. 97 Chapter 981 (p. 10) and Episode 987, Who's-Who is seen with some of his present subordinates.