Explore the fascinating connection between stars, black holes, and gravitational waves in this comprehensive lecture on gas-embedded binaries. Delve into the matter background, supermassive black holes, and the pre-main sequence of stellar evolution. Examine late evolutionary stages and various formation mechanisms of celestial objects. Investigate merging binaries and their role in producing gravitational waves. Gain insights from an expert in theoretical physics as part of the Kavli Institute for Theoretical Physics' Blackboard Lunch series, designed to foster cross-disciplinary understanding and maintain the unity of theoretical physics.