Okay, the frame as a narrative device. Most writers have at least heard of it. There’s a story within a story. But let’s look at this from a mystery perspective:
- A crime happens or is discovered (in the case of a long-past crime).
- The main action of illustrating the crime happens on another level, for example, the past or a fictional story (even if the crime happens in the “present” frame of the overall story).
- The crime is not resolved in the other level of the story, regardless of where it occurs.
- An action must be taken in the “present” for the crime to be resolved–the truth brought to light, the crime solved/resolved, or even hiding the crime entirely.
This is stuff like Possession, The Arabian Nights (a crime story rather than a mystery per se, really), Heart of Darkness, Wuthering Heights (there’s a lot of “he stopped loving her today” sensationalist fiction in this vein, of course), Baudolino, A Study in Scarlet, A Devil in Velvet, and Shutter Island. I would say that A Daughter of Time doesn’t fit this, because the sections of the past never really take over the narrative.