Captain 3-D is the last of the people of D, who were exterminated 50,000 years ago by the Cat People (currently led by Tigra). He has been preserved in 2-D, within the pages of the Book of D, which has been protected by a human gaurdian since the demise of his own people. The current guardian is Danny Davis who runs a used book shop. Captain 3-D seems to posses the ability to traverse from 2-D to 4-D. In 3-D, his belt is able to use 4-D energy to give him the power of flight. He is an exceptional fighter besides that, and he may have knowledge of his people's advanced technology.