Stars are disappearing! As the Defenders float in space, Cloud shows them an empty vacuum that once hosted celestial bodies. Realizing that a being called Star-Thief is responsible, the Defenders kick off a mad dash to stop them!
After Cloud's fit at the end of last issue, she teleported the Defenders into the middle of interplanetary space. They are kept alive inside Cloud, who now remembers who she is. She is actually a nebula--a cloud of interstellar dust that will eventually become a star--instead of a Earthly weather cloud. She also remembers why she came to Earth in the first place. As a sentient nebula, she noticed that the stars in this area of space are vanishing.
However before she can finish her explanation, they are interrupted by a fleet of alien ships. They go inside one of the ships and, after some mix-ups, realize that the aliens are friendly. (The three main ones look like the Three Stooges, and the Defenders call them by the Stooges' names.) They explain that their own sun is one of the missing stars. It disappeared and their planet froze.
Outside the ship, a strange planetoid appears. It is Kubik, a sentient Cosmic Cube. He explains that he had run into Cloud in space, and wanted to help with the missing stars. He knew about Captain American from their last encounter at Captain America Annual #7 and told Cloud that maybe Cap can help her. She traveled to Earth in search of him but was waylaid by the Secret Empire, which brainwashed her and led her into eventually meeting the Defenders.
Back in the present, Kubik assumes Captain America's form and goes with the Defenders in search for the mystery of the vanishing stars. They are found by the Star-Thief, an angry psychic face who wants to extinguish all the stars around it, and threatens them before leaving them.
The Defenders eventually find the source of the missing stars, and the Star-Thief's transmission. After battling the planet's army and the Star-Thief's apparition's once more, they reach the planet's palace.
Going in, they find a little princess in a comatose state. She had become blind and now doesn't want anything to shine. With her natural psychic power, she had managed to suction Kubik's power from afar without him knowing it, and used it to hide the stars in a pocket universe. Angel, who is blind himself, enters her mind with the help of Cloud, and convinces her to stop destroying the Universe. With his power once again under his control, Kubik returns the stars to their places. Cloud tells the others that she will now return to her natural nebula form, and says goodbye--to Iceman especially.
An initially humorous epilogue has Sassafras being attacked by the many goofy holograms inside the Defender's base...until Manslaughter shows up and saves him by turning off the systems.