International Ocean Discovery Program Expedition 392 drilled three sites on the Agulhas Plateau and one site in the Transkei Basin in the Southwest Indian Ocean in Ferb-March 2022 (Fig. 1). This region was positioned at paleolatitudes of ~53°–61°S during the Late Cretaceous (van Hinsbergen et al., 2015), within a new and evolving oceanic gateway between the South Atlantic, Southern Ocean, and southern Indian Ocean basins. Sedimentary and basement sequences were successfully recovered from the Agulhas Plateau sites U1579, U1580, and U1582, and a thick sedimentary sequence was recovered in the Transkei Basin at Site U1581 (Fig. 2). Drillcores from these four sites provide a wealth of new data to (1) determine the nature, origin, and bathymetric evolution of the Agulhas Plateau; (2) significantly advance the understanding of how Cretaceous temperatures, ocean circulation, and sedimentation patterns evolved as CO2 levels rose and fell and the breakup of Gondwana progressed; (3) document long- and short-term paleoceanographic variability through the Late Cretaceous and Paleogene; and (4) investigate geochemical interactions between igneous rocks, sediments, and pore waters through the life cycle of the Agulhas Plateau large igneous province (LIP). Importantly, postcruise analysis of Expedition 392 drill cores will allow testing of competing hypotheses concerning Agulhas Plateau LIP formation and the role of deep ocean circulation changes through southern gateways in influencing Late Cretaceous–Paleogene climate evolution.