Changing your detective name
Click your name in the top corner → Settings → Detective name.
Your detective name is shown on the leaderboard. Change it in Settings: click your name in the top corner, then Settings. Names are 2–24 letters, numbers or spaces, and must be unique.
Separately, each case asks what the suspects should call you. That's just for the story.
Didn't answer your question? Ask in the chat at the bottom right.