Twilight of the North
Investigate helps to discover information and uncover secrets. It is possessed by thieves and guardsmen alike, and sees widespread use by anyone who makes it their business to learn things firsthand, through concentration and scrutiny rather than passive observation. It covers all sorts of information-gathering activities such as eavesdropping, searching for clues, examining records, and conducting surveillance.
Investigate is extremely useful for Creating an Advantage, as you can use it to learn a person’s secrets, the details of a place or object, or the weaknesses of an organization (creating all sorts of interesting and useful Aspects). It can also be used to Overcome an obstacle when a character needs to discover or confirm an established piece of information.