Theseus grasped a scarlet thread to trace his way back through the maze.
After the blood of the red heifer had been sprinkled by a priest, the carcass was totally immolated with cedarwood, hyssop, and a scarlet thread.
They promised that on their return as conquerors, she and her family would be protected by a "scarlet thread" she was to fasten to her window.
They tied scarlet thread around neighbours' wrists, put up flags along the roadside and erected a metal sign declaring their new status.
The lyrically extroverted modernism that flourished between the wars might be seen as a possible alternative path for contemporary music, a scarlet thread out of the 20th-century stylistic labyrinth.
Biohazards such as third-party blood, vomit, sputum or faeces can fatally contaminate a crime scene and impede the pursuit of what Holmes called the "scarlet thread of murder".
During that busy year, she notched up several more films, starting with top billing in the thriller The Scarlet Thread, where an ambitious Laurence Harvey proved as disconcerting as Lockwood.
The traumas of war run like a scarlet thread throughout the film, which opens with a shot of a tall and smoking ruin of rubble and captures a tone of an impoverished and rebuilding nation repressing real wounds with a stiff upper lip.
As Holmes says in A Study in Scarlet, "There's the scarlet thread of murder running through the colourless skein of life, and our duty is to unravel it, and isolate it, and expose every inch of it". That, perhaps, is at the heart of our fascination with Holmes, and with science.
It is striking to note the scarlet thread that runs through Bonhoeffer's life and thought from his first days as a preacher and teacher to his last days as a political prisoner.
Whether terrorism, the banality of people 'going postal' or those enacting their psychotic fantasies on innocents in the lunchroom, the scarlet thread that binds them is access to guns.
