Final Crisis: Requiem serves as an expansion of events in Final Crisis #1, particularly one major event that was dealt with all-too quickly: the death and aftermath of J’onn J’onnz, the Manhunter from Mars.
The issue opens on Mars at the funeral of the Manhunter, his coffin surrounded by heroes that knew and/or served with him over the years, with Superman delivering the eulogy.
In flashback, the Manhunter’s last moments are replayed as Effigy and Dr Light, having drugged him with pyro-tranquilisers take him to meet Libra.
As Libra stabs him (as seen in Final Crisis #1), J’onn lashes out both physically and psionically, momentarily convincing the assembled villains that the Justice League have arrived to save him. Unfortunately, Libra realises what’s going on and stabs him once more. As Libra slashes J’onn’s throat, he sends out a telepathic message to some of his closest friends.
Superman, Batman, Black Canary, Green Lantern Hal Jordan and Gypsy all receive J’onn’s telepathic cry, each of them bursting into flames, though they all remain unharmed. Some time later, Nightwing discovers the body of J’onn hanging in the Rose Center for Earth and Space, pinned to the model of Mars.
J’onn’s corpse is taken to the League’s headquarters where Green Arrow and Green Lantern reminisce about him. Later, Batman, Superman, Green Lantern, Gypsy and Black Canary all find themselves recording J’onn’s life in one manner or another, compelled to do so by the last telepathic cry of their friend. As a parting gift, J’onn had entrusted them with not only his own history, but that of the Martian race, now forever lost.
After the funeral, the five friends say their last farewells, leaving J’onn’s spirit to rest with those of his family on his home planet.