A study using JWST/NIRSpec data reveals that massive quiescent galaxies at z ~ 2 show three distinct star formation histories (SFHs): (1) galaxies quenched early with old stellar populations; (2) galaxies quenched recently after a flat or bursty formation history; and (3) galaxies quenched recently after a major starburst. Most recently quenched galaxies show neutral gas outflows and ionized gas emission, consistent with active galactic nucleus (AGN) activity driving rapid quenching. The study predicts a number density of massive quiescent galaxies at z = 4-6 of (1.5-6.0) × 10⁻⁵ Mpc⁻³. Two old galaxies in the sample appear to have formed and quenched at z > 6, possibly as descendants of early post-starburst galaxies. The study also finds that ejective AGN feedback is a dominant mechanism for quenching at z ~ 2. The results suggest that AGN activity drives multiphase gas outflows, leading to rapid quenching. The study highlights the importance of detailed SFH reconstruction to distinguish between rapid and slow quenching mechanisms and to identify post-starburst galaxies. The findings support the idea that AGN feedback is a key driver of galaxy quenching at cosmic noon.A study using JWST/NIRSpec data reveals that massive quiescent galaxies at z ~ 2 show three distinct star formation histories (SFHs): (1) galaxies quenched early with old stellar populations; (2) galaxies quenched recently after a flat or bursty formation history; and (3) galaxies quenched recently after a major starburst. Most recently quenched galaxies show neutral gas outflows and ionized gas emission, consistent with active galactic nucleus (AGN) activity driving rapid quenching. The study predicts a number density of massive quiescent galaxies at z = 4-6 of (1.5-6.0) × 10⁻⁵ Mpc⁻³. Two old galaxies in the sample appear to have formed and quenched at z > 6, possibly as descendants of early post-starburst galaxies. The study also finds that ejective AGN feedback is a dominant mechanism for quenching at z ~ 2. The results suggest that AGN activity drives multiphase gas outflows, leading to rapid quenching. The study highlights the importance of detailed SFH reconstruction to distinguish between rapid and slow quenching mechanisms and to identify post-starburst galaxies. The findings support the idea that AGN feedback is a key driver of galaxy quenching at cosmic noon.