Along the rugged Welsh coastline, Bobby Jones finds a dying man at the bottom of the cliffs. As Bobby tries to ease his final moments, the dying man utters a mysterious question.

Following a shocking death thought to be suicide, Bobby and Frankie are convinced it was murder. Together, they hatch a plan to infiltrate Frankie into the home of their prime suspect.

Frankie and Bobby shift their suspicions to the menacing figure of Dr James Nicholson, bringing the pair one step closer to answering the cryptic question of why they didn't ask Evans.

Risking life and limb for each other, and for the answer to the puzzle, Frankie and Bobby enter the lions' den to confront the conspiracy's true mastermind - and in so doing, finally unlock the mystery behind the cryptic question: Why Didn't They Ask Evans?