We all know the sound. That crazy, trilled electronic whistle that dips into a whoop. Or it starts in a trough and shoots up into the super stratosphere. It’s the sound of UFOs and mad science. It’s the sound of the theremin.

This week on “Picture Perfect,” we anticipate a hands-off Halloween with selections from four films enhanced by Leon Theremin’s visionary instrument.

“The Thing from Another World” was one of two seminal science fiction scores written in 1951. (The other was Bernard Herrmann’s “The Day the Earth Stood Still.”) On the soundtrack, the theremin acts as a musical counterpart to James Arness’ rampaging humanoid carrot. This was unquestionably composer Dimitri Tiomkin’s wildest hour; he never wrote anything like it again.

“The Thing” and “The Day the Earth Stood Still” may have been the most influential, but “Rocketship X-M” was the first. The film was rushed into production to beat George Pal’s “Destination Moon” to theaters in 1950. It was shot in just 18 days! The unlikely plot has the crew of a moon expedition blown off course to Mars. Interestingly, the composer was none other than Ferde Grofé – he of the “Grand Canyon Suite” fame.

Far more reputable, but still not wholly comfortable with its science, is Alfred Hitchcock’s “Spellbound,” from 1945. Gregory Peck plays an amnesiac, who may or may not have committed murder, and Ingrid Bergman is the psychoanalyst who falls in love with him. The film is of greatest interest for its production design, which features dream sequences conceived by Salvador Dali, and for its score, by Miklós Rózsa.

Hitchcock disliked the music – he thought it got in the way of his direction – but Academy voters disagreed, and the score earned Rózsa the first of his three Academy Awards.

Closer to our own time, Howard Shore incorporated the theremin into his Mancini-esque music for “Ed Wood,” released in 1991. The film is Tim Burton’s love letter to the grade-Z director of “Plan 9 from Outer Space.” “Plan 9” is widely regarded as the worst movie ever made (worse even than “Rocketship X-M”).

Make contact with the theremin – its distinctive, extraterrestrial timbre, you’ll recall, conjured without physical touch – on “Picture Perfect,” music for the movies, THIS SATURDAY EVENING AT 6:00 EDT, on WWFM – The Classical Network and wwfm.org.

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