In Exile

When Narcissa Malfoy goes missing, leaving behind her wand, a suicide note, and an empty bottle of belladonna, the aurors are content to call it open and shut suicide. Draco Malfoy strongly disagrees, and will do whatever it takes- and accept help from whomever it takes- to find out what happened to his mother. Even if that help means asking Hermione Granger to help him look.