The adventure can take place in a slightly shifted reality, where everybody has a totem (an animal guardian). The totem should be chosen randomly and not by the player, it is ok if "Gorflin the Large," a gigantic and aggressive barbarian, has a mouse for a totem.
These totems will assist the characters in small way. It is up to the characters to determine how to get the assistance; the animals won't solve mysteries for the characters only supply the clues. The character may even have a dream where his or her totem actually speaks to them and reveals some sort of clue.