The Sorcerers is a 1967 British science fiction horror film directed by Michael Reeves, starring Boris Karloff, Catherine Lacey, Ian Ogilvy, and Susan George.
The One Sheet poster (27″×41″) for the US release features PLINC’s Davison Kaleidoscope. This variation of Dave Davison’s Impacta is distinguished by letterforms that are filled with a hypnotizing whirl pattern. A year after this poster was issued, in 1968, PLINC presented their Psychemat technique. It allowed the application of various similar psychedelic patterns to any suitable typeface design (see examples under the Psychemat tag). Kaleidoscope appears to be one of several precursors in which the effect is built in, and not applied in a second step.
Davison Kaleidoscope as shown in Photo-Lettering’s One Line Manual of Styles, 1971