Reaction of the 1,2-disilylene, [{ArC(NDip)2}Si]2 1 (Dip=2,6-diisopropylphenyl, Ar=4-C6H4But), with CO proceeds via insertion of CO into one Si−N bond and Si−Si bond cleavage, to cleanly give the bis(silylene), {ArC(NDip)2}Si(:)O (Formula presented.) Ar 2, under ambient conditions. The reaction can be partially reversed when solutions of 2 are subjected to UV irradiation. The five-membered heterocyclic fragment of 2 represents the first silicon analogue of an “abnormal” N-heterocyclic carbene (aNHC), a view which is substantiated by a computational analysis of the compound. Reaction of 2 with [Mo(CO)6] under UV light affords the chelate complex, [Mo(CO)4(κ2-Si,Si-2)] 3, while reaction with [Fe(CO)5] gives the unusual silyleneyl bridged complex, [{Fe2(CO)6}{μ-Si[(NDip)2CAr]}2] 4. The same coordination complexes can be accessed by reaction of 1 with [Mo(CO)6] or [Fe(CO)5] under UV light. As is the case for aNHCs, d-block metal complexes of bis(silylene) 2 could prove useful as bespoke catalysts for organic transformations. © 2022 Wiley-VCH GmbH.