The activation of CS2 is of interest in a broad range of fields and more particularly in the context of creating new C‐C bonds. The reaction of the dinuclear ytterbium(II) complex [Yb2L4], 1, (L = (OtBu)3SiO‐) with carbon disulphide led to the isolation of unprecedented reduction products. In particular the crystallographic characterization of complex [Yb2L4(µ‐C2S2)], 2 provides the first example of an acetylenedithiolate ligand formed from metal reduction of CS2. Computational studies indicate that this unprecedented reactivity can be ascribed to the unusual binding mode of CS22‐ in the isolated “key intermediate” [Yb2L4(µ‐CS2)], 3 which is resulting from the dinuclear nature of 1.