Marla Latham works for R.J. Brande helping to manage his businesses. He was appointed by Brande to be the Adult Advisor to the Legion of Super-Heroes after the United Planets made some subtle threats of investigations towards the team of teenagers. Marla's duties included the training of new members, and he developed a series of tests and procedures that were later incorporated into the curriculum of the Legion Academy. His first (and favorite) Legion recruit was Ultra Boy, whose membership test was to travel with Marla to Superboy's time and uncover his secret identity. Ultra Boy passed this test, and having bonded with Marla, modeled his own costume after Marla's outfit.
Eventually, though, Marla grew unhappy with his advisor role. Once the Academy was established, he felt unnecessary and like a crutch for the Legionnaires, who were asking his advice on problems that they should have been handling themselves. Fearing that his presence would hold them back, he asked Brande to arrange for a reassignment. After Marla's transfer, Brande delayed replacing him until he saw how well the Legionnaires did on their own, and eventually deemed the position obsolete.
Marla rarely interacted with his former charges after that. But when Ultra Boy was framed for murder by Pulsar Stargrave, Marla intervened to make sure that the murder investigation was handled as honestly as possible.
When Brande fell victim to Yorggian fever, Marla oversaw Brande's convalescence.
Marla went into semi-retirement shortly before Brande's death, but he assisted with Brande's estate afterwards, and still keeps an informal watch on the Legionnaires.