- Max: " Well, your mother and I, we never intended to live outside the law."
- Brennan: "I don't understand. Then why did you?"
- Max: "I can't tell you why. Not yet. Certain people are out there... still alive... could get hurt. And after all I've done, I don't want to hurt anyone else."
- — The Carrot in the Kudzu
It is revealed that he and his wife were career criminals who went into hiding after committing many crimes as fugitives. Its eventually revealed that the origins of their criminal activity had to do with threats from Marvin Barlow.
Along with his wife, his crimes included robbery, of which they were noted to be far more intelligent than their fellow gang members, applying this knowledge to rob banks. However, money wasn't only the commodity of which they stole, but robbed Ohio First Savings and Loan deposit box where information compiled by Augustus Harper against the FBI was stored. Thus, after Augustus Harper's death, the information became incriminating evidence of FBI corruption. Garrett Delaney sought to kill Russ to not only lure Max out of hiding, but to permanently silence Max, but ended up getting murdered. Max gave Temperance a tape from her mother that was supposed to be for her sixteenth birthday, and, on a separate occasion, a ring from her grandmother. Today, Brennan still wears that ring.
When his children were 7 and 3 years old respectively, Max changed the identities of his family to protect them from the gang of violent bank robbers with whom he and his wife worked as career criminals. He becomes "Matthew Brennan", his wife Ruth becomes "Christine Brennan", and their children Kyle and Joy become "Russ Brennan" and "Temperance Brennan". As Matthew Brennan, Max worked as a science teacher, while his wife worked as a bookkeeper.
A few days before Christmas in their home in Ohio in 1991, when Russ was 19 years old and Temperance was 15, Max and his wife, after having just spotted one of their old associates from the gang Vince McVicar, left for the safety of their children by leading McVicar away, and never returned to the home in order to keep Russ and Temperance hidden. McVicar tried killing Ruth with a bolt stunner. Though his wife died from a subdural hematoma in 1993 as a result from the attack, Matthew continued living in hiding for years, until Russ' life was threatened. Between the time he went into hiding and season 2, Brennan determined that he had plastic surgery, chin and cheek implants, and even changed the color of his eyes.
He first shows up in Season 2, pretending to be a Priest, to get closer to Brennan. Russ already knew who he was. He adopted the name of Father Toby Coulter as an alias when he first met Booth and Brennan at the seminary. The real Father Coulter is one of Max Keenan's friends during his criminal career who was 90 years old at the time who is confined in bed with Alzheimer's in a convalescent home at the seminary which gave Max the opportunity to use his name as an alias.
When he was finally brought to trial for the murder of Deputy FBI Director Robert Kirby ("The Verdict in the Story"), Max was cleared of the charges, but only on a technicality; after forensic evidence determined that Kirby had actually been killed by a small ornamental dagger in Brennan's apartment rather than Matthew's trademark copper pipe, the defense counsel pointed out that it was equally plausible for Temperance or Russ Brennan to have killed Kirby, prompting the charges to be dismissed due to there being no sufficient evidence to specifically incriminate any potential suspect (Although Booth himself risked jeopardizing that defense by stating that Brennan could not commit murder based on his personal and professional experiences with her).
In The Bone that Blew, Max got a job at the Jeffersonian as a science teacher, a job he had before he went into hiding.
In Season 5 episode The Goop on the Girl, Max reveals that he is in contact with some of his late wife's relatives, when he invites Brennan's cousin, Margaret, to Christmas dinner. He also attempts to kill Heather Taffet during her trial, when he perceives her as a threat to Dr. Brennan in The Boy with the Answer. This leads Booth to believe Max has not abandoned his criminal ways, and to suspect Max's involvement in two murders in Season 6 (those of Heather Taffet and a member of his bowling team), although Max is exonerated in both cases. He also indicates that he has begun dating again and that he always expected Brennan and Booth to "settle down together" ("The Bullet in the Brain"). In Season 6's The Change in the Game, Bones and Brennan join his bowling team undercover after one of the team is murdered. Max is confined to a wheelchair and cane due to falling out of bed during sex but helps solve the case.
In Season 7, he offers to take care of Booth and Brennan's daughter Christine. Despite Brennan's initial reservations, she eventually agrees. In the Season finale, he helps Brennan and Christine get out of town, after Christopher Pelant frames Brennan for the murder of her friend, Ethan Sawyer. When confronted by Booth, Max explains that Brennan has to stay outside the system, if she's to be safe. He also encourages Booth to stay in the system and help prove Brennan's innocence. During the three months they are on the run, Max and Brennan learn all they can about Pelant, and eventually discover the grave of one of his first victims.
Later on in Season 8, Max returns after Brennan is shot while working in the lab. While recovering in the hospital, Brennan gives him a message from her mother, telling Max that her mother knew that the first gift he gave to her was stolen, which takes him by surprise as no one knew that aside from him.
In Season 9, Max returns to attend Brennan and Booth's wedding, and to attend Christine's birthday party. During the next few seasons, Max becomes close to Brennan and Booth. He attends lots of family gatherings. He also takes Christine and Hank, Booth and Brennan's son, most days to school and after, while their parents are at work.
In "The Putter in the Rough," Max is arrested for grave robbing by the Ohio State Police. Booth discovers that the grave Max robbed was that of Marvin Barlow, a man who was on the FBI's Ten Most Wanted List until Max dug him up as no one knew that Barlow was dead. Booth gets the charges against Max dropped, but he refuses to explain himself and is ordered out of his daughter's life by Brennan. He subsequently drops out of contact again, but later returns with Booth to explain himself. Max gives Brennan a ring that he had retrieved from Ohio in the coroner's evidence locker. The ring is one of Brennan's that Barlow had stolen while she was sleeping as a child. Barlow had used it as proof that he could kill Brennan any time he wanted unless Max did as he said. Barlow's threats were the reason Max and Ruth started their criminal lives, but Barlow disappeared twelve years before, promting Max to come back and confirm it. It's one of many occasions where Max had been looking over his shoulder to make sure that her family was safe. Now understanding the truth, Brennan allows her father to stay and gives the ring to Christine as a gift from her grandfather.
In Season 12 Episode 2 ("The Brain in the Bot") Max drops what looks like a hospital wristband. It is eventually revealed in The Scare in the Score that he had a pacemaker installed due to some heart issues he was experiencing and he kept it from Brennan for a time to keep her from worrying about him.
Max is among the last of six known casualties linked to a revenge plot against Booth. When Max orchestrates a last-minute counter strike against assassins sent to kill his grandchildren, Christine and Hank Booth, he kills all assassins but is seriously wounded. He dies while in recovery from surgery, flatlining after sharing the memory of a peaceful dream involving Temperance, Russ, and their mother, Christine.
Max is characterized as a very protective father who would stop at nothing to protect his children. This becomes a source of conflict for Brennan and Booth who has had to arrest him several times, albeit rather apologetically. Despite this, Max approved of their relationship early on, even before Brennan and Booth themselves acknowledged that they were in love with one another.
Despite his malicious past he is a very kind, charming man who is very loving and affectionate with his children. It has been stated that his main problem is that his attitude consists of a moral framework that allows him to commit any action, including murder, so long as it is done for what he perceives as the right reasons; Booth himself has noted that Max has never killed anyone who did not definitively deserve to die.
Known Crimes and Victims
- Presumably committed numerous crimes prior to the start of the series.
- Committed an unknown robbery for which he was sent to Cook County Jail in 1966.
- Unnamed Prisoner (Stabbed with a copper pipe in self-defense in 1966, survived.)
- Robbed a Piggly Wiggly in Carbondale, Illinois in 1978.
- Robbed Ohio First Savings and Loan in Dayton in 1978 (Three fatalities; committed with a gang. ):
- Two innocent bystanders
- One State Trooper
- Seven additional bystanders (injured)
- Garrett Delaney (Shot in the head with a .22 handgun, gutted and set on fire.)
- Robert Kirby (Stabbed in the back of the head with a misericorde, gutted and set on fire.)
- Veleska Miller (Tortured for information on Booth.)
- Heather Taffet (Attempted to kill her.)
- Christopher Pelant (Attempted to kill him.)
- Marvin Barlow (Grave Robbing, charges were dropped by Booth.)
- Goran Milovic (Shot in the chest.)
- Andre Belgrader (Shot in the chest.)
Victims by Proxy
- No mention of his murder of Garrett Delaney was mentioned after Judas on a Pole, even during his trial in The Verdict in the Story, suggesting that Kirby's murder was the only murder they could forensically connect to him.
- In a later episode, Booth states that Max never killed any civilians or honest cops, suggesting that Max wasn't responsible for the fatalities of the robbery