10 Genius Movie Tricks You Totally Take For Granted
2. Filming A Plane Crash With Rear Projection & A Water Slide - Foreign Correspondent
And finally, a deep, deep cut now, but one that absolutely deserves to be spotlighted.
Alfred Hitchcock's 1940 spy thriller Foreign Correspondent features an outstanding shot where a plane crashes into the ocean after being shot down by a German destroyer, and at the moment of impact the cockpit becomes filled with water, soaking the cast.
This is depicted by a locked-off camera pointed at the cockpit, and while it's easy to appreciate that the watery background was a classic case of a video being rear-projected behind the cockpit set, how was the cockpit flooded with water for real?
A lot of work went into this - more than most anyone who's seen the movie will likely appreciate.
For starters, the footage of an aircraft diving over the ocean was projected onto a sheet of rice paper, and behind the sheet were two giant tanks of water, each connected to a water slide aimed towards the sheet.
And so, the water was timed to release from the tanks just as the projected footage got close to the water, with the water then shooting through the rice paper screen and flooding the cockpit set for real.
Though you can see the screen peel back for a few frames as the water gushes in if you scrub through it painstakingly, it's nevertheless an incredibly creative effect and one that's aged spectacularly well over 80 years later.