The recent discovery of gravitational waves by LIGO was a stunning validation of Einstein's General Theory of Relativity. The European Space Agency LISA mission is a set of space-borne gravitational detectors separated by millions of kilometers that will directly observe the stretching and squeezing of spacetime. In this public lecture, the science behind the mission, the technological challenges, and the impact of the results on our understanding of the universe will be discussed. This event is kindly supported by the Instititue of Physics (Ireland) & UCD College of Science. The event is free to attend, but requires registration via EventBrite. This event is suitable for a general audience interested in Astrophysics, Gravity and the European Space Agency.