Imaginasi. Idea. Insepsi.

Noun1.inception - an event that is a beginning; a first part or stage of subsequent events

origination, origin

beginning - the event consisting of the start of something;
germination - the origin of some development;
cause - events that provide the generative force that is the origin of something;
prelude, overture, preliminary - something that serves as a preceding event or introduces what follows.

A contemporary science-fiction-action-thriller story set within the architecture of the mind. Only made by one Chris Nolan.