Drought and floods affect the structure, composition, and the function of global environments and thus human societies. Although several studies exist on both droughts and floods, studies on whether droughts can be a means to cause floods or vice versa are lacking in the literature. However, it has been repeatedly said that after a severe drought season, there is heavy rainfall and thus flooding. Using different global terrestrial ecosystems from across the globe, understanding the underlying mechanisms, evolutions, and drivers of how droughts can abruptly cause flooding or vice versa on a global scale representing drought-flood hotspot regions from both the Northern and Southern Hemispheres is indispensable. Considering drought hotspot areas across the globe such as the 2000s Australia’s Millennium drought, and the 2010/11 Horn of Africa drought that experienced large-scale flooding in the aftermath of drought is crucial. Subject to analysis and interpretations, the study findings of drought-flood underlying interactions reveal major contributions to the growing field of drought hydrology for future policymaking.