WARNING: The following contains spoilers for The Old Guard: Tales Through Time #2, from Eric Trautmann, Mike Henderson and Daniela Miwa, on sale now.
Before The Old Guard was a Netflix feature, the original comic series focused on Andy and her group of immortals having to escape the clutches of the sinister Steven Merrick. He worked their handler, Copley, and Booker, sewing seeds of betrayal as he wanted to capture and experiment on them to harness eternal life for himself.
He was pretty sadistic, so much so the Netflix film turned him into a corporate tycoon so he could use the immortals as guinea pigs in a pharmaceutical project. While the Force Multiplied comic sequel didn't dwell on the tyrant, Tales Through Time #2 ironically reveals his creation is due to one of Andy's crew.
This story, "Strong Medicine," has Booker in 1870 in Colorado awaiting Andy. The place is a mess, though, and seeing as there's no gold rush yet, he resorts to drinking in the saloon. Part of it is to kill time, but en route to town, he saw a doctor, Banning, hanging after a skirmish.
This triggered memories of his past where he was hanged for deserting Napoleon so Booker hits the bottle. But in the bar, he runs afoul of Eamon Coyle's gang. Eamon's the one who killed Banning as he wanted the doc to save his misfit brother, Keenan, which just couldn't happen. Eamon's cussing out everyone, Booker included, and admits they've got a British doctor coming to fix his kin.
Booker finds it funny as Eamon's either too drunk, stupid or in denial to accept his brother's gone, which leads to another scuffle. In the melee, Eamon blows Booker's brains out in front of the new doctor and then proceeds to try to lynch the physician. But Booker's Wolverine-like healing powers activate and he gets up, missing an eye and with blood on his skull, which stuns the barman. He then grabs his sword and pistol, heading to save the doc.
He cuts a bloody scene, savagely slaughtering the gang and rescuing the man. The doc's in shock as he saw Booker get killed and quickly jumps on his cart to flee the chaotic scene. He jokes this is a story to inspire his descendants and shockingly, the side of his cart reveals he's Milford Merrick. He's a healer, scholar and scientist, which means Booker just saved the life of Steven's ancestor.
By letting Milford live, Book saved Steven's bloodline, paving the way for him to sell his allies out in a bloody civil war. That led to so much torture and pain, with Booker also being thrown into exile, and he learned that the old maxim that 'no good deed goes unpublished' in a very literal sense.