Vertigo
This was my first Hitchcock movie ever(!!) and now I'm almost kicking myself for nearly 30 years of negligence.
Vertigo's portrayal of the realistic, slow-creeping human spiral into obsession and fantasy in pursuit of rectifying trauma and personal glory is piercing. Rarely do movies draw the link to reality fluidly, and James Stewart's performance as Scottie was borderline frightening and solidly discomforting.
Not knowing much about Hitchcock, the commentary on how Vertigo is his projection stemmed from the working relationships with his actresses is quite fascinating.
I would highly recommend watching this in UHD if possible – the colors of the flowers, the interior, and neon lighting of San Francisco were stunningly beautiful.