At the beginning of the series, Matt is the "black sheep" of the O'Dare family, unknown to his siblings on the payroll of local criminals and himself a murderer and thief. However, he undergoes a strange vision which, with the help of the Shade, he comes to realize means he is the reincarnation of Brian Savage who was a lawman in Opal City back in its lawless, Wild West days.
Matt O'Dare was once a good cop. But as he himself admitted to his sister Hope, he was partnered with a bent guy. Matt continually advised him to get clean, but he simply shrugged it off. One day, he ended up sick and he couldn't make a delivery for the mob. It was an important delivery, so he begged Matt to do the delivery himself so there would be no actions taken. Matt reluctantly complied and he from then on was forced to make the same deliveries under the penalty of being outed. He from then on went in a spiral of self-destruction; extortion, women, losing evidence and other criminal actions became old hat for him. Despite this, he maintained the facade of being an O'Dare, one of Opal City's most decorated cop families. But eventually, the dreams caught up with him.
In dreams, a man dressed as an Indian told him of honor and dreams and how he had soiled his name. It all started making sense when he volunteered to protect the frail first Starman, who had been injured in an attack on his observatory. In this attack, he met the Shade, who attacked him and his brothers to draw Ted Knight into his Darklands. Later on, the dreams increased in frequency until he got involved in the Demon Quest. Along with the Shade and Jack Knight, he was dragged into Hell by a magical poster. Before being sucked in, he implored Shade to preserve his good name until he could return and clear it himself. He was unsuccessful until he mentioned his dreams. Shade then realized Matt was the reincarnation of an old friend, Scalphunter, one of Opal's first lawmen. He complied with Matt's request and dove after him into Hell.
In Hell, Matt was confronted with a vision of Scalphunter, who accused him of destroying both their names with his actions. To cleanse his reputation, Scalphunter gave him the chance to forfeit his soul in exchange for all the souls contained within the poster. Matt agreed, as did Shade and Jack in their respective visions. Matt was released, as were all of the souls. He and Shade then applied to the task of eliminating all records of Matt's past indiscretions. During the Infernal Doctor Pip's quest to bomb Opal, his sister Hope confronted him with the knowledge of what he had done; Matt simply vowed to change and as a sample he admitted to wiping out large sections of Opal's underworld with Shade's help. Grudgingly, Hope agreed to give Matt a chance and kept her silence. Conversely, Matt made good friends with the Shade and listened to his stories about Scalphunter.
In Jack Knight's absence, he was one of Opal's great heroes against crime along with his sister. Then he caught in the air the first faint waves of the storm that was the Grand Guignol. Together with hope, he investigated and found out of the first symptoms of the storm that was to come. He then conferred with Hope and his brother Barry. Barry asked whether they had reported their findings to Clarence, their older brother and Opal City's police commissioner. Upon realizing they hadn't, Barry shot them with a silenced pistol and kept them prisoner in his supporting role of Simon Culp's final plan to kill the Shade.
Matt was released during Culp's televised announcement of the destruction of Opal, and scattered with the other heroes to thwart Culp's plan. First, they released the powerless Shade from the Spider's grasp, by pitting his own marksmanship against his archery. Later on, he joined Clarence, Hope and his brother Mason to find Faith, Clarence's wife, and Charity, Mason's girlfriend, whom Barry had abducted. Upon finding them in a meat storage facility, the O'Dares engaged in a gunfight against Barry's men, decimating them. Barry himself survived until he appeared when Clarence was releasing his wife, and dove in to take a shot intended for Clarence, killing Barry with his revolver.
Matt was swiftly taken to an Opal hospital in the aftermath of the Grand Guignol, but it was too late. While the doctors operated, he was far too gone and only had time left for a final conversation with his family, Jack and the Shade. Then, he commented he felt his soul would continue to roam, until it was no more. He revealed that he would be reincarnated as a future Starman, and Jack comforted him by telling him he had met that future Starman and how he would be a hero of many worlds. Soothed by the fact he would again return to see his beloved city, Matt passed away surrounded by friends and family, and was given a hero's funeral after the storm had been weathered and the Grand Guignol was no more.
Matt O'Dare was created by writer James Robinson and artist Tony Harris. He first appears in Starman #1.