This is the emoji of a men detective, who wears a gray hat. His clothes are well-ironed, and the collar is standing up to cover the half-face. On some platforms, it also has a magnifying glass in his hand, looks mysterious and capable.
🕵️♂️ usually used to represent the detective, or the things suspense, reasoning, and so on.
Sometimes, people would use this emoji to represent Shelock Holme. Genderless version🕵, male version
🕵️♀️. Related emojis:
🧐👮💡🔍