This paper aims to explore Deleuze’s linkage with Spinoza, in order to suggest that his theory of immanence was strongly influenced by a life-long study on this philosopher. The present investigation focuses on the key-concepts used by Deleuze in his interpretation of the Ethic: causality, theory of distinction, attribute, expression and power. The immanent causality, opposed to the Plotinus’s emanative causality, needs a theory of distinction to not fall in the indeterminate. This distinction found the triad substance-attributes-modes, connected to each other through the expression. This interpretation is then short compared with three others, known by Deleuze and very influential at the time, namely those of Delbos, Alquié and Gueroult. Finally, the power confirms the articulation of the triad pointing out the individual’s autonomy in front of God. This connection is the base of Deleuze’s intuition on the intimate relationship between transcendence and immanence. Professor Challenger is the conceptual character who helps us in this research.