At long last, the prodigal son has returned to Supernatural. The CW show's Jan. 30 episode delivered a heavenly surprise when Jack (Alexander Calvert) finally resurfaced with a renewed purpose. It turns out that Billie (Lisa Berry) brought back the young Nephilim to defeat Chuck (Rob Benedict) once and for all. Nobody was happier to see the sandy-haired half-angel back in his rightful place than Castiel (Misha Collins), who'd been mourning his death all season.