This episode faithfully follows everything that has happened in the season without relying on it. All you need to know is what happened when Hercules first met Ioulus' jester doppelganger. We're told something has happened since, Armageddon pt. 2 is acknowledged. And we're allowed to experience the story itself. Herc jumps into the netherworld he had seen once before, meets Jester Ioulus and together the go back to the mirror universe to A. Free the gods of our world and B. Take down the Empress. The entire time Ioulus insists 'when this is over we split up and go our separate ways. Turns out the one time he did try to be a hero, like Hercules, it didn't work. And he is even more convinced that he is a coward. But he proves himself as faithful a companion, self-flagellating as he is.
The only problem is that Hercules should have known. When he finds Earth-2 Ioulus alive in the wasteland between worlds, despite the fact that the Ioulus he knew is dead, Hercules discovers and reasons that 'in the netherworld I guess the rules don't apply'. He should have known that, from Armageddon pt. 2. But it was still great story-telling. And the happiest of endings. I won't give anything away but the final scene is...beautiful.
