Supergirl 3x17 "Trinity"<br /><br />Still reeling after learning about Lena's secret, Supergirl asks Guardian for a favor that could alter his relationship with Lena forever. Meanwhile, with all three Worldkillers united, Supergirl and the team brace for an epic battle.<br />Directors: Caitlin Parrish, Erica Weiss<br />Writers: Jerry Siegel (based on characters created by), Joe Shuster (based on characters created by) | 6 more credits »<br />Stars: Melissa Benoist, Mehcad Brooks, Chyler Leigh
