In 'Hello, Who's Adventure?', players assume the role of an over-caffeinated detective named Sam Spade who just can't seem to remember anyone's names. One morning, Sam wakes up to find a mysterious letter on their desk and a strange string of numbers that might lead to the solution of a baffling case. As players navigate through a quirky city filled with zany characters—including a talking cat and a conspiracy theorist librarian—they must gather clues, engage in witty dialogues, and solve humorous puzzles that reveal the truth behind the bizarre happenings in town. Will Sam discover who is behind the letter and ultimately the masked individual orchestrating chaos in the city?