Detective stories depend on the depiction of mysterious characters unraveling complex mysteries. This research investigates the development of the detective archetype through an examination of how memories and personal histories of iconic figures such as Sherlock Holmes and Lisbeth Salander have been depicted from past works to present-day stories. The archetype of the Intellectual detective who uses memory and deductive logic to solve mysteries was first introduced in the early detective literature through Edgar Allan Poe’s Dupin stories. Sherlock Holmes continued to enhance this custom by utilizing precise recollection and systematic techniques in solving crimes. His skill in piecing together past events from incomplete evidence established a standard for future fictional investigators. On the other hand, modern pieces such as Stieg Larsson’s Millennium series present figures such as Lisbeth Salander, whose troubled background and intricate personal story give a new meaning to the detective stereotype. Salander’s storytelling delves into topics such as trauma, identity, and societal exclusion, mirroring contemporary cultural trends towards more complex depictions of investigators.This paper examines how the portrayal of memory and personal history in detective fiction has changed over time, shifting from using memory as a cognitive aid to delving into themes of trauma and identity in current works. This research helps to explain the impact of memory on the formation of characters and complexity of storylines in detective fiction.