Professor Layton

The first three games follow the adventures of Professor Hershel Layton and his apprentice Luke Triton, while the subsequent three games and film are prequels, focusing on how Luke and Layton met and their original exploits. Later installments follow the escapades of Layton's children and their respective allies in settings old and new. Each title features a series of puzzles and mysteries provided by the citizens of locales that the main characters explore. It is not necessary to solve all the puzzles to progress, but some are mandatory, and at certain points in the game a minimum number of puzzles must be solved before the story can continue. (Source: Wikipedia)