Diane Arliss accompanied her brother Todd Arliss to Doctor Dorcas' laboratory, hoping he could, indeed, cure her brother's crippling spinal injury. She did not know, however, exactly how Dorcas planned on doing so. When she discovered it involved harming the recently captured Sub-Mariner, she was torn, but her loyalty to her brother prevailed -- until she saw Dorcas' cure transform her brother into Tiger Shark. She helped Namor regain his freedom in exchange for his promise to help her brother regain his humanity.
Diane Newell was created by Roy Thomas
and John Buscema
in 1968 and first appeared in Sub-Mariner