The Punisher's greatest enemy is his own past. Even when he's not being haunted by the death of his family or racked with guilt from his own actions in the military, he's being hunted by men who already believed he was dead. Spoilers! Some former members of Project Cerberus, Frank Castle's former paramilitary outfit, are the clear villains of The Punisher – but how long has Frank Castle been trying to escape the shadow of this group? Is Project Cerberus from the comics, or was this crew invented for The Punisher's jump to television?
Project Cerberus has never been on the right side of ethical, but the group hits a new low once Frank Castle discovers the truth behind their operation. Even when Frank Castle was a member of the team, they were a part of such despicable actions as executing an Afghani police officer, but their drug-running habits take the cake for horrible actions. (Frank wasn't aware that they were operating without congressional approval, nor how immoral their actions were.)
While Project Cerberus has played a huge part in Frank Castle's backstory, the organization is actually invented for the television show. Project Cerberus does not appear anywhere in the Marvel comics – even if some of the most high-profile members of this group have a long history with The Punisher comic series.
Project Cerberus turned their backs on former members Frank Castle and David "Micro" Lieberman after commanding officer William Rawlins aka Agent Orange suspected that they leaked footage of the execution. Rawlins, along with former Cerberus member Billy Russo, begin the hunt for Frank Castle after they suspect he's still alive. While The Punisher uses Project Cerberus to connect all of these characters, each of these characters originates separately in Marvel comics.
Despite William Rawlins having the built-in supervillain alter ego of "Agent Orange," this corrupt government agent exists only by his real name in The Punisher comics. Billy Russo, on the other hand, is known as "Jigsaw" and was a street-level criminal called on to help carry out the hit on Frank Castle's family. "Micro" and Frank Castle find each other in the comics when they try to take on a similar enemy – Daredevil's Kingpin – as opposed to having been linked to Project Cerberus once he was sent the execution video that forever put him on William Rawlins' hit list. All of these characters come from very different backgrounds in the comics, but the show worries more about getting these characters in the same place than getting their backstories entirely accurate.
Of course, while the characters start out in different places in the comic, that doesn't mean that they'll stay on that path. Billy Russo bears little resemblance to his comic book counterpart, but that may come to an end if he gets a few facial scars to resemble the horrifying criminal Jigsaw. William Rawlins is currently running a major underground drug operation, but there's no telling if he'll start working with Russia as he does in the comics. Most surprisingly, Micro ends up getting killed by Frank in the comics after turning to drug sales to finance assassinations. While it doesn't look like Micro will be turning on Frank soon in the series, there's still a chance their relationship could change over the course of a full season or two.
Project Cerberus puts a lot of major Punisher characters in the same circle, allowing them to already have a familiarity with each other instead of finding ways for them to come together. It's a smart adaptation choice, and honors the history of the characters even if it diverges from each character's origin story. The Punisher takes more than a few liberties when adapting its characters, but it doesn't tiptoe around putting it's main characters in dangerous situations. Project Cerberus may have been invented for the show, but it feels right at home in the violent world of The Punisher.