Netflix’s The Umbrella Academy ended season 2 with a cliffhanger that saw the Hargreeves siblings confronted with the Sparrow Academy, a superpowered group Reginald Hargreeves seems to have adopted in an alternate timeline. A flying green cube is among the seven members of the Sparrows and the introduction of the object — whose name is Christopher — actually makes Five’s transformation from season 1 all the better.
In The Umbrella Academy season 2, Five was training to master his ability to teleport and time travel. Growing impatient one day, Five time-traveled to the future and wound up stuck there with no way back to the present. Decades later, Five remained nameless and stranded, turning into a bitter, cynical man in his 50s. When he finally managed to figure out the formula to return to the moment he left, Five was restored to the body he had as a teenager (much to his frustration) and stayed that way for the first two seasons of the show.
Of course, being a 50-something in a teenage body is no walk in the park, but one can argue that it's far better than being a floating cube. In a description released by Netflix, Christopher is “a telekinetic cube of unknown origin. He can turn the room freezing cold and induce paralyzing fear. He acts as the Sparrows’ consulted oracle who hands out incredible advice and serves as the family mediator.” The fact that the mysterious cube has a name suggests that Christopher was once a human; that he can be consulted as an oracle indicates he can speak. It’s possible that he was turned into a cube — be it through some strange event or experimentation — and couldn’t be turned back, leaving him in this state forever.
Should that be the case, then Christopher’s situation mirrors Five’s conundrum. However, it actually makes the latter’s problem of being stuck in his teenage body pale in comparison to living out his life as a cube. Five is still a human, after all. Despite being talked down to and treated like the teenager he looked like on the outside (something he despised profusely), Five could still live normally, weaving in and out of society without garnering much attention. As a cube, however, Christopher can’t do the same. Who knows? The Umbrella Academy season 3 might give Five a new outlook on his situation, which he’s attempted and failed to fix from the start.
What exactly transpired to transform Christopher into a glowing green cube is unclear, but it seems obvious that it’s due to Reginald’s experiments. He didn’t exactly adopt the two sets of kids so that he could be a model father and the past two seasons of The Umbrella Academy have proven how neglectful and abusive he was during their youth. Ultimately, season 3 can explore this further. As it stands, potentially being experimented on and raised by Reginald is the one thing Five and Christopher have in common and perhaps they can at least bond over that.