In an investigation of instructional treatment by learner-variable interaction, 437 college Ss were divided between filmed and live physics lecture demonstrations. Immediate- and delayed-recall criteria were applied. Using prior knowledge of physics and 14 other learner characteristics as independent moderator variables, a series of 2 x 3 x 3 unweighted means analyses indicated that attitude toward instructional films, ascendancy, responsibility, numerical aptitude, verbal aptitude, past experience with entertainment films, and past use of college library instructional films interacted significantly with instructional treatments, primarily on the immediate-recall criterion. Prior knowledge of physics modified most of these effects. Attitudes toward entertainment films and toward physics, emotional stability, sociability, total personality self-evaluation, academic achievement, and unspecified past experience with instructional films did not interact with instructional treatments.