The Mr Black Knows Everything meme is based on the character Mr. Black from the animated series Johnny Test. As a high-ranking government secret agent often seen alongside his partner Mr. White, Mr. Black is known for his stoic demeanor and access to top-secret information. The meme usually features him appearing as if he has just uncovered a classified secret or is watching someone's every move. It has become a popular format on social media platforms like TikTok and X (Twitter) to joke about government surveillance, knowing a niche fact, or exposing a friend's secret habits.