Supergirl 3×22 “Make It Reign” Season 3 Episode 22 Inside – SUPERGIRL PREPARES FOR BATTLE – Supergirl (Melissa Benoist) learns the true depth of Serena’s (guest star Anjali Jay) nefarious plans for Earth. Supergirl, Mon-El (Chris Wood) and Alura (guest star Erica Durance) must devise a plan to stop her before Serena gets to Earth. J’onn (David Harewood) prepares to say goodbye to his father (guest star Carl Lumby). Armen V. Kevorkian directed the episode written by Ray Utarnachitt & Cindy Lichtman (#322). Original airdate 6/11/2018.