Mahou Senki Lyrical Nanoha Force

The story appears to be centered on the investigation of the Book of the Silver Cross, an ancient Belkan magical tome. Tohma Avenir, whilst travelling, discovers a girl named Lily Strosek trapped inside a construct. When rescuing her, she gives Tohma an amulet that gives him access to a new Device power. However, unbeknownst to them, there is another with a similar Device causing massive damage and injury, leading to an investigation by the Time Space Administration Bureau.