With thousands of worlds beyond our solar system unveiled, the three extremely large telescopes currently under construction will dramatically advance the study of exoplanetary systems in the next decades. The unprecedented size of these telescopes will permit high-contrast imaging of planetary companions to host stars in the solar neighborhood at orbital separations closer than 1 au, and high-dispersion spectrographs will open a window to detailed investigations of the structure and dynamics of exoplanet atmospheres, including weather patterns and cloud properties. In the most favorable cases, these instruments will be able to probe the atmospheres of terrestrial planets within the habitable zone of nearby stars, bringing us much closer to answering one of the most fundamental scientific questions: (where) does life exist beyond Earth?