Through their strong winds and explosions, massive stars enrich the Universe with the building blocks of life, including the carbon in our cells and the oxygen we breathe. However, not every massive star explodes; some form black holes. Moreover, we now know that most massive stars live with close companion stars that can change their fate and could lead to universal signals. With the recent discovery of gravitational waves, stars with invisible companions, and automated observations of exploding stars, astrophysicists can finally test the existence of these signals and better understand the final fate of massive stars.