Morpheus is the captain of the hovercraft Nebuchadnezzar and the biggest believer of the prophecy of The Oracle. Morpheus, believing that he is destined to find "The One" that will bring an end to the war between humans and machines and the destruction of The Matrix, frees the mind of Neo and begins his journey to do just that.
Previously romantically involved with Niobe, Morpheus went on to live a very priest-like lifestyle. After the events of The Matrix films (as depicted in The Matrix: Path of Neo) and Enter The Matrix, Morpheus played a key role in the continuing existence of The Matrix and Mega City in the ongoing and tense armistice between the humans and machines (as seen in The Matrix: Online). Neo was a strong proponent for returning the remains of Neo to the humans. As a way of silencing him, Morpheus was supposedly killed by The Assassin, however it was later revealed the bullets used by The Assassin only disrupted Morpheus' transmission into The Matrix, making it near impossible for him to re-enter. There are also those that believe that Morpheus is truly dead and that his RSI (Residual Self Image) is being manipulated by The General in an attempt to sway humans back toward war with the machines.