In summary, we have developed a highly chemo-, regio-, and stereoselective TM-free strategy for the hydrocyanation of internal, unbiased alkynes. The method rests on a simple aminephosphine dual-catalytic system that merges reversible alkyne-allene isomerization with HCN transfer, introducing a novel mechanism for selectivity control through the inherently regioselective hydrocyanation of the allene intermediate. The methodology enables an efficient synthesis of vinyl nitriles (37 examples) under mild conditions, achieving excellent yields (up to 97%), rare anti-stereoselectivity (up to >20:1) and broad functional group tolerance.