Related Clues:

• It might have a twist
• Book basis
• It might consist of a 19-Across
• Whodunit component
• Central story line
• Movie's story line
• It might thicken
• It usually thickens
• Underhanded plan
• Whodunit foundation
• Whodunit kernel
• It might thicken when given a twist
• Churchyard unit
• Secret plan
• Cabal's creation