When Does "Prey" (2002) Take Place?
"Prey" is a science fiction novel written by Michael Crichton that released November 25th, 2002. So when is "Prey" set?
It takes place in the year:
We know this because in the first chapter when Jack Forman watches a recording of his wife Julia Forman’s scientific demonstration (which he’s told was recorded earlier that day), he notices the automatic timestamp in the corner of the video.

2002 AD
We know this because in the first chapter when Jack Forman watches a recording of his wife Julia Forman’s scientific demonstration (which he’s told was recorded earlier that day), he notices the automatic timestamp in the corner of the video.
As he narrates, "When I turned to switch off the TV, I looked down at the time code running at the bottom of the image. Numbers were spinning, ticking off hundredths of a second. Other numbers to the left, not spinning. I frowned. One of them was the date. I hadn't noticed it before, because it was in international format, with the year first, the day, and the month. It read 02.21.09. September 21. Yesterday. She’d recorded this demo yesterday, not today."
In this order, the numbers "02.21.09" represent September 21st, 2002 AD. It cannot be September of 2002 BC for several reasons. For our purposes, let’s stick to the fact the Forman house has a television set, which was invented in the 1920s-1930s AD.
If it’s one day later, it is certainly September 22nd, 2002 AD at the start of the story. Since the narrative only covers a single week, it also ends around September 28th, 2002 AD within the 2002 AD calendar year.