When Does "Frequency" (2000) Take Place?
"Frequency" is a science fiction film written by Toby Emmerich that released April 28th, 2000. So when is "Frequency" set?
It takes place in the year:
We know this because the story is a dual-timeline narrative: father Frank Sullivan is shown in 1969 AD and son John Sullivan is shown in 1999 AD. At one point, John says to the villain, "You went down 30 years ago, pal. You just don't know it yet.", referring to the actions his father is taking in October of 1969 AD. The phrase "30 years" is used throughout.

1969 AD/1999 AD
We know this because the story is a dual-timeline narrative: father Frank Sullivan is shown in 1969 AD and son John Sullivan is shown in 1999 AD. At one point, John says to the villain, "You went down 30 years ago, pal. You just don't know it yet.", referring to the actions his father is taking in October of 1969 AD. The phrase "30 years" is used throughout.
10.1969 + 30 = 10.1999.
Furthermore, there's a superimposed time setting title card reading quite early: "OCTOBER 10ᵀᴴ? 1999".
Additionally, there's a radio broadcast in the very first scene that can be heard announcing, "? tomorrow for the opener of the 1969 World Series ?". The real-world series of baseball games the 1969 World Series was held from October 11th, 1969 AD to October 16th, 1969 AD. So it must be October of 1969 AD.
Furthermore, the prologue includes its own title card that reads, "OCTOBER 10TH. 1969".
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