In this paper, Plato’s notion of the sudden moment is fully explored. In the Parmenides, the “now” (nun) and the “sudden” (exaiphnês), it is argued, refer to one and the same entity from the distinct perspectives of timeless Being and temporal Becoming, respectively. This interpretation tallies well with, and enriches, the Platonic views on time and eternity found in the Timaeus. Finally, the paper highlights the pivotal role of the third deduction, where the sudden moment appears, for an understanding of the entire dialectical exercise of the Parmenides.