Zodiac and an Italian movie. “The tenth victim”

A few weeks ago, an American researcher on the Zodiac case, “ShaneV”, made an interesting finding.

On the website newspapers.com, an archive containing a digital copy of tons of newspapers printed in the United States over the last two centuries, he found advertising dating back to 1966 for a movie that dealt with the topic “of choice” for the infamous serial killer “Zodiac”.

Hunting human beings.

Locandina del film “Il gioco più pericoloso”

“The most dangerous game”
Premise. In his first cipher mailed in three parts to different newspapers of the San Francisco Bay Area on July 31, 1969, Zodiac writes:

"I like killing people because it so much fun
it is more fun than killing wild game in the forrest
because man is the most dangerous animal of all..."

Many researchers here have seen a mention the the movie “The most dangerous game”, based on a short story by Richard Connell.
The plot of the 1932 film sees the two main characters, a couple (like Zodiac’s favorite victims) shipwrecked on a remote island owned by a Russian nobleman, Count Zaroff. The two youngsters soon discover that the count has a passion for hunting. In particular, for hunting humans.
Thus the protagonists from guests become fleeing preys.

“The tenth victim”
December 20, 1969. Officers at the San Francisco postal office postmark an envelope addressed to the lawyer of the celebreties Melvin Belli.
The front reads: “MERY XMASS”. It contains a missed letter, typical mispelling of the so called “Zodiac”.
The first part of the letter says:

"Dear Melvin,
This is Zodiac speaking I wish you a happy Christmass.
The one thing I ask of you is this, please help me. I cannot reach out
of help because of this thing in me wont let me. I am finding it extremely dif-
icult to hold it in check I am afraid I will loose control again and take my nineth
& posibly tenth victom..."

“The tenth victim”… is this a real count? Or is the serial killer exaggerating, as the police believe, who attribute 5 murders to him?
54 years pass and ShaneV comes across a suspicious coincidence.
In some US newspapers from 1966, he found ads for an Italian film entitled “The Tenth Victim”.

“La decima vittima”, in Italian, is a movie by Elio Petri starring Marcello Mastroianni and Ursula Andress, which was released in Italy in 1965 and in the United States in 1966.
Topic?
Human beings hunting.
In a dystopian future set in Rome, murder is legalized on a voluntary basis and becomes a sport for a few “chosen ones”.
Beautiful Ursula Andress is a famous killer who must reach the most coveted goal of a hunter, “the tenth victim”, in fact. The prey is Marcello Mastroianni.
Did Zodiac want to refer to this Italian film in his letter to Belli?
It would seem so.
And it is not the only “movie” coincidence between Zodiac and Italy.