It has been speculated upon, that the Zodiac Killer may have theatrical leanings, having previously paraphrased The Mikado twice before in the 'Little List' letter mailed on July 26th 1970. But would a killer familiar with The Mikado so flagrantly misspell one of its most popular acts, turning 'Titwillow' into 'tit willo', unless by intention, and if so, what was the intention. This phrase from The Mikado comes immediately after 'Signed, yours truley' as if the verse was designed to infer a name.
The first thing to consider is that 'Willo' is a variation of the term Willow, and contains the name 'Will', short for William. Bearing in mind this was chosen as a verse, referring to 'tit willo' three times, it's unsurprising then, that the name William can be found three times between the creators of The Mikado and The Exorcist. The Exorcist was directed by William Friedkin and adapted for screenplay by William Peter Blatty, based on his 1971 book. One half of The Mikado was William Gilbert.
However, when the Whitechapel murderer signed off the 'Dear Boss' letter, he stated 'Yours truly, Jack the Ripper', not a William in sight. That is until we consider either the Halloween Card, mailed only once removed from this correspondence on October 27th 1970 or the actual term 'Willo'.
The Zodiac added a pumpkin to the Halloween Card and in the Exorcist Letter either deliberately or inadvertently separated 'Titwillow' into two parts, leaving 'Willo'. It doesn't take much searching to discover that one of the main features of Halloween is the carved pumpkin, often referred to as a Jack-O'-Lantern named after the flickering light of Will-O'-the-Wisp.
Which, if any, the Zodiac Killer was referring to is unknown, but both can be inferred as signatures of the killer, bearing in mind the introduction of 'yours truly' and the absence of any obvious signature by the author, as well as their shared commonality of 'flickering lights' under the Halloween tradition.
'The names will-o'-the-wisp and jack-o'-lantern are explained in etiological folk-tales, recorded in many variant forms.
In these tales, protagonists named either Will or Jack are doomed to haunt the marshes with a light for some misdeed. One version, from Shropshire, recounted by K. M. Briggs in her book A Dictionary of Fairies, refers to Will the Smith. Will is a wicked blacksmith who is given a second chance by Saint Peter at the gates to Heaven, but leads such a bad life that he ends up being doomed to wander the Earth. The Devil provides him with a single burning coal with which to warm himself, which he then uses to lure foolish travellers into the marshes.
An Irish version of the tale has a ne'er-do-well named Drunk Jack or Stingy Jack who makes a deal with the Devil, offering up his soul in exchange for payment of his pub tab. When the Devil comes to collect his due, Jack tricks him by making him climb a tree and then carving a cross underneath, preventing him from climbing down. In exchange for removing the cross, the Devil forgives Jack's debt. However, because no one as bad as Jack would ever be allowed into Heaven, Jack is forced upon his death to travel to Hell and ask for a place there. The Devil denies him entrance in revenge, but, as a boon, grants Jack an ember from the fires of Hell to light his way through the twilight world to which lost souls are forever condemned. Jack places it in a carved turnip to serve as a lantern.'
Will-O'-the-Wisp is also a 1931 novel by French writer Pierre Drieu La Rochelle, about a man serving in the military, before ending up in a mental institution for depression and ultimately committing suicide. It was adapted for film as 'The Fire Within' in 1963.
It can be easily inferred that the mention of suicide in the letter and this being the, or one of the last letters by the killer, that the Zodiac Killer was preempting his own demise. However in the next paragraph he returns to the usual sense of foreboding, stating he will "do something nasty" if the note is not published. Hardly consistent with a killer about to take his own life.
The combination of The Exorcist and The Mikado, one would think, was there by design and had purpose. That purpose being, to project a name in our direction or some form of clue, just like the Halloween Card. On the other hand, this is the impression we often get from much of his correspondence, and as yet it largely remains a mystery as to its true meaning, other than to taunt and belittle.
Let us hope that the answers come soon for everyone concerned, in particular the families and friends of the victims, and one day the flickering lights of the Zodiac Killer can ultimately be extinguished forever.
An extension to this article can be found here http://www.zodiacciphers.com/zodiac-news/name-dropper