SPOILER WARNING: This article contains major spoilers for “Far From the Tree,” the latest episode of Supergirl.
In "Far From the Tree," the latest episode of Supergirl, J'onn J'onzz made a shocking discovery: his father Myr’nn is alive. Both J'onn and Kara headed to Mars following M'gann's cry for help, and there they discovered that Myr'nn had been held in White Martian captivity for centuries.
During a raid on a White Martian base, M'gann and her forces came across a prison camp that was still in operation. In the prison camp, M'gann's resistance discovered another Green Martian: none other than J'onn's father Myr'nn. "I brought you here because I didn't think you'd believe me unless you saw this for yourself," M'gann said of their discovery, showing J'onn a livefeed of Myr'nn in their holding cell.
"Myr'nn J'onzz is the high religious leader of the Green Martians," M'gann explained, to which one of her recruits added, "Not even the worst of the Whites would kill the Prime Servant of H'ronmeer," the Martians' god.
As J'onn recovered from his shock, M'gann revealed their true purpose for bringing him to Mars: Myr'nn knows the location of the Staff of K'lar, a psychic weapon. Should the White Martians find it, they would be able to locate and destroy the resistance. As such, the resistance brought J'onn back to Mars so that he could coax the location out of his father.
However, convincing Myr'nn that J'onn was who he said he was took more effort than they anticipated, as Myr'nn was convinced that J'onn was actually a White Martian masquerading as his son. J'onn was ultimately able to convince Myr'nn when he brought him to his old home and shared a memory of his daughters with him. Myr'nn gave up the location of the Staff just in time for J'onn, Supergirl and the resistance to defeat the White Martians. The resistance then handed the Staff over to J'onn, who brought it back to Earth for safekeeping.
The Staff isn't the only thing J'onn brought back to Earth. He also brought Myr'nn with him, so that they might live together in peace once more.
Airing Mondays at 8 p.m. ET/PT on The CW, Supergirl stars Melissa Benoist as the Girl of Steel, David Harewood as Martian Manhunter, Mehcad Brooks as Jimmy Olsen, Chyler Leigh as Alex Danvers and Jeremy Jordan as Winn Schott, with appearances by Calista Flockhart as Cat Grant and Tyler Hoechlin as Superman.