Brin Londo was the son of the amoral scientist Doctor Mar Londo. In order to create the ultimate fighting machine, Doctor Londo performed experiments on his own son, transforming him into a human canine. Brin Londo escaped from his father's laboratory facility and dashed off into the forests of Rawl. His father sent seeker robots to track him down, but Brin, having reverted to a state of primal savagery, destroyed them all. 
The Legion of Super-Heroes visited this world and encountered Doctor Londo's robots in the forest. Brin arrived and destroyed several more of them, but then snatched Saturn Girl and took off into the woods. Saturn Girl established and empathic bond with Brin and realized that there was more to this savage than met the eye. Using her powers, she succeeded in calming him down, and Brin reverted into a near-human state. He returned with Saturn Girl to the Legion whereupon they learned about his father's experiments. Following an incident at Doctor Londo's laboratory, Brin decided to leave the planet forever. He was subsequently offered membership into the Legion of Super-Heroes and took the code-name Timber Wolf. 
Timber Wolf's first official mission as a legionnaire pitted him against the superhuman power house known as Drax. Complicating matters were Drax's two monstrous pets who began their own tirade of destruction across the Earth. Timber Wolf partnered himself with Phantom Girl as they searched for the creatures in the sewer systems. Timber Wolf's instinctive machismo girded him to protect Phantom Girl, but this did little more than annoy her than impress her. Still, a bond began to develop between the two, even when they found themselves prisoners in the Phantom Zone.
A later mission brought Timber Wolf back to his home world of Zuun. He was part of an important expedition to find trace samples of Zuunium, the rarest mineral in the galaxy. Zuunium was the only thing that could save their colleague Brainiac 5, who was suffering from a worsening case of mental erosion due to being separated from his native Coluan collective. Timber Wolf and Superman fought through a phalanx of mining robots, but they were able to successfully procure enough Zuunium to help Brainiac. 
The most harrowing experience in Timber Wolf's life took place only two years later. Doctor Mar Londo used invisible nanites that could travel through space and time and infected Brin Londo on Earth, stimulating his limbic system. This caused Timber Wolf to lapse into uncontrollable fits of rage. His changes in behavior were so severe that he could not distinguish between friend or foe. Doctor Londo manipulated Timber Wolf into attending an Interplanetary convention at Heisenberg-7. As Doctor Londo demonstrated his advances in genetic mutation with his new Bio-Golems, Timber Wolf sprung from the audience and attacked him, seemingly killing him. In truth, Doctor Londo faked his death in the hopes of luring Timber Wolf back to his laboratory on Rawl. As it turned out however, Timber Wolf was apprehended by the Science Police and put on trial. Timber Wolf offered nothing in his own defense, even though several of his close allies in the Legion were certain that he was innocent of any wrongdoing. Timber Wolf could not determine with any degree of certainty that he didn't in fact murder Doctor Londo. During his trial, Brin Londo lost control of his abilities once again and tore through the courtroom. Chameleon Boy, convinced of his teammate's innocence, disguised himself as Timber Wolf, allowing the real Timber Wolf time to escape.
Timber Wolf returned to Heisenberg-7 to investigate the crime scene on his own. He picked up several familiar scents in the convention chambers, the strongest of which, was his own. Convinced of his own guilt, Timber Wolf went feral once again and fought against his fellow Leggionaires who tried to contain him. Timber Wolf fought past them and took a cruiser back to the planet Rawl. There he found his father Mar Londo still alive. Doctor Londo explained his actions to him, proclaiming that he wanted to help Timber Wolf. He wanted to stabilize the balance between man and wolf with the hopes of making Timber Wolf the leader of his own private army. Timber Wolf fought against his father and his Bio-Golems, but just when he thought he had finally captured the renegade scientist, he discovered that this too was a ruse. The real Mar Londo was monitoring affairs from a remote location, leaving another of his advanced clones on Rawl to interact with Timber Wolf. Though frustrated beyond measure, Timber Wolf was cleared of all charges, but he always lived in fear that one day the man would lose control once again and give way to the beast. 
As a result of his father's experiments, Brin Londo is always at risk of losing control of his feral side. Though he has the benefit of close friends to help him through his struggles, he never knows when he might suddenly lose control. His greatest fear is that he might unwittingly harm those closest to him.
- This version of Timber Wolf is exclusive to the continuity of the Legion of Super-Heroes animated series and the Legion of Super-Heroes in the 31st Century comic book adaptation. In the animated series Timber Wolf was voiced by Shawn Harrison.
- Though Timber Wolf's powers are very similar to that of a Werewolf, he is actually a result of science gone awry, and is not a werewolf in the traditional sense.
- During the course of the series, a romantic interest between Phantom Girl and Timber Wolf was hinted at, but never fully realized.
- 28 Appearances of Brin Londo (Legion of Super-Heroes TV Series)
- 4 Images featuring Brin Londo (Legion of Super-Heroes TV Series)
- 4 Quotations by or about Brin Londo (Legion of Super-Heroes TV Series)
- Character Gallery: Brin Londo (Legion of Super-Heroes TV Series)