When C-3PO (voiced by Anthony Daniels) appeared in Star Wars: The Force Awakens with a red arm and no explanation, audiences went mad… or at least actively curious about the sudden change to the beloved droid. Now, a new one-shot comic (a single issue story) from Marvel tells the story of C-3PO’s crimson limb.

The first hint as to the origin of C-3PO’s arm came in the Force Awakens visual dictionary, which explained that he wears it in memory of a droid who sacrificed himself during a mission. Touching, but that’s it. Now, in Marvel’s new Star Wars: C-3PO #1, written by James Robinson, Tony Harris, and Joe Caramagna and out today on comic shelves, follows the golden protocol droid and the story of that fateful assignment.

Having captured a First Order doid named Omri, who has information on the location of Admiral Ackbar, C-3PO and a group of Resistance soldiers and droids crash land on an unknown planet. The human crew is wiped, leaving the droids on their own. They discover a downed TIE fighter with a distress beacon and journey across the planet before it’s too late.

One by one the droids are killed by planetary hazards, from quick sand to predatory beasts, leaving just C-3PO and Omri. The two enemies stranded together engage in an existential debate about their place in life as droids. What follows is something very profound and poignant. (Warning: Spoilers are below.)

Omri is a nihilist, who ponders why it’s so acceptable to erase a droid’s memory (recall at the end of Revenge of the Sith when Bail Organa casually orders C-3PO’s memory wiped). If droids are capable of bravery, honor, and sacrifice — if R2-DR isn’t that, then the other droids who died in this issue stresses this point — then why erase what made them to become who they are?

It’s an age-old question, just applied to droids. How many lives can one ever live? What kind of person — indeed, this comic treats droids like people — can you be if you’re subject to someone else’s decisions? Omri’s hostility towards Threepio isn’t his own choosing, but comes from programming.

The red arm is what makes this comic almost sublime. At one point Threepio’s arm is ripped off by a giant creature, and soon afterwards the TIE fighter is within reach. But an acid rainfall forces Omri and Threepio to take shelter. Omri decides to give Threepio the information he’s storing and sacrifices himself to activate the beacon, knowing the rain will destroy him. As the rain falls, Omri’s silver paint peels, revealing another life he’s forgotten where Omri lived a red droid.

No dialogue or speech bubbles necessary. The images say it all.

After he’s rescued, Threepio takes Omri’s arm for himself as not just a keepsake for a friend, but to remember even if another day will come when his memory is erased.

Man, The Force Awakens was good, but C-3PO #1 is something else entirely. It’s out now on shelves if you wanna pick it up.

Photos via Marvel, io9, Disney