The first example of a Donor-spacer-Acceptor tryad, based upon a molybdenum-ene-1,2-dithiolate unit as the Donor and a naphthalene-diimide as the Acceptor, has been synthesized and its photophysical properties investigated. Synthesis required the preparation of a new pro-ligand containing a protected ene-1,2-dithiolate bound through a phenyl linkage to a naphthalenetetracarboxylicdiimide (NDI) group. Deprotection of this pro-ligand by base hydrolysis, followed by reaction with [Cp2MoCl2], produced the new dyad [Cp2Mo(SC(H)C(C6H4-NDI)S)] (2). Electrochemical studies showed that 2 can be reversibly oxidized to [2](+) and reduced to [2](-), [2](2-), and [2](3-). These studies, augmented by UV/vis, IR, and electron paramagnetic resonance (EPR) spectra of electrochemically generated [2](+) and [2](-), show that the highest occupied molecular orbital (HOMO) of 2 is ene-1,2-dithiolate-based and the lowest unoccupied molecular orbital (LUMO) is NDI-based; these conclusions are supported by density functional theory (DFT) calculations for the electronic ground state on a model of 2 which also showed that these two parts of the molecule are electronically distinct. The dynamics of the excited states of 2 in CH2Cl2 solution were investigated by picosecond time-resolved IR spectroscopy following irradiation by a 400 nm similar to 120 fs laser pulse. These investigations were complemented by an ultrafast transient absorption spectroscopic study from 420 to 760 nm of the nature of the excited states of 2 in CH2Cl2 solution following irradiation by a 383 nm similar to 120 fs laser pulse. These studies showed that irradiation of 2 at both 400 and 383 nm leads to the formation of the [(Cp)(2){Mo(dt)}(+)-Ph-{NDI}(-)] charge-separated state as a result of a cascade electron transfer initiated by the formation of an (NDI)-N-1* excited state. (NDI)-N-1* rapidly (ca. 0.2 ps) forms the local charge transfer state [Cp2Mo(dt)-{Ph}(+)-{NDI)(-)] which has a lifetime of about 1.7 ps and decays to produce the ground state and the charge-separated state [(Cp)(2){Mo(dt)}(+)-Ph-{NDI}(-)]; the latter has an appreciable lifetime, about 15 ns in CH2Cl2 at room temperature.