There is a fanciful notion of what may be achieved using communication where at least part of the intended message passes beneath the recipient's threshold for conscious perception. Typically, a character is manipulated by the clever insertion of imperceptible cues in the audio or video they see.

Examples:
In "Max Headroom: 20 Minutes into the Future" (1985), the Network 23 television network used a new form of subliminal advertising, called blibverts, to prevent their viewers from channel surfing.

References:
https://en.wikipedia.org/wiki/Subliminal_stimuli