D.N. Angel centers around Daisuke Niwa, a 14-year-old boy who discovers he is the descendant of a long line of phantom thieves. On his 14th birthday, Daisuke undergoes a transformation triggered by his feelings for Risa Harada, a girl he has a crush on. When his emotions overwhelm him, he turns into Dark Mousy, a legendary phantom thief with supernatural abilities. This transformation is tied to a family curse that has persisted for generations, compelling the Niwa males to become phantom thieves until they can retrieve a set of mystical artifacts known as the Hikari artworks.

Dark Mousy is a charming and confident alter ego, skilled in stealing valuable items and evading capture. His primary target is the Hikari collection, which holds significant power and is guarded by the Hikari family. The Hikari family, particularly Satoshi Hiwatari, a classmate of Daisuke, is determined to stop Dark and protect the artworks. Satoshi possesses his own alter ego, Krad, a being of light who serves as Dark’s nemesis. The dynamic between Dark and Krad is rooted in a centuries-old conflict between light and darkness, adding a layer of tension to the story.

As Daisuke navigates his dual identity, he becomes entangled in a complex web of relationships. Risa Harada and her twin sister, Riku Harada, both develop feelings for Daisuke, though their affections are complicated by his connection to Dark. Risa is infatuated with Dark, while Riku grows closer to Daisuke, creating a love triangle that adds emotional depth to the narrative. Meanwhile, Daisuke’s grandmother, Emiko Niwa, and his mother, Harada Niwa, provide guidance and support, though they often withhold crucial information about the family curse and its origins.

The series explores themes of identity, love, and destiny as Daisuke struggles to balance his ordinary life with his responsibilities as a phantom thief. The pursuit of the Hikari artworks drives much of the plot, with each artifact revealing more about the history of the Niwa and Hikari families. The story also delves into the origins of Dark and Krad, uncovering their intertwined fates and the tragic events that bind them together.

D.N. Angel combines elements of romance, fantasy, and action, with a focus on character development and interpersonal relationships. The interplay between Daisuke and Dark, as well as the evolving dynamics between the main characters, forms the core of the narrative. The series maintains a balance between lighthearted moments and darker, more introspective themes, creating a multifaceted story that appeals to a wide audience.