Rückkehr der Finsternis (Return of Darkness) is the first book of the Die Sieben Gezeichneten campaign (The Seven Marked Ones). It compiles the original adventures Alptraum ohne Ende, Unsterbliche Gier, and Grenzenlose Macht into a single volume. It also adds a campaign overview, pre-generated characters, and background information.
Warning: Spoilers ahead!
The campaign is suitable for characters starting with roughly 5000 points of experience. They start at a fair in Baliho from where they set out to investigate the burning of a priest of Tsa by a mob in the small village of Dragenfeld. They compete with a group of Prios followers and an inspector of the secret police. Arriving in Dragenfeld the adventurers find the village destroyed and the surrounding lands withered. The temple of Tsa has been desecrated by an evil wizard. When he is destroyed, the characters find out that they have been moments too late. The spirit of the long-dead Borbarad has been released into the world to wreak havoc in the following adventures. At the end of the events, the eye of one of the characters changes into a glowing red ruby which makes him the first of the Marked Ones. This concludes the first adventure Alptraum ohne Ende (Endless Nightmare).
The second adventure is Unsterbliche Gier (Immortal Craving). It seems at first not related to the events of Alptraum ohne Ende. The adventurers are called to the duchy of Weiden where they reveal and fight an infestation of vampires. It was caused by the dark elf Pardona in her attempt to steal enough life force to form a new body for Borbarad's spirit. At the climax of the adventure, the characters battle Pardona and the arch vampire Walmir von Riebeshoff in their sinister tower, and one of the characters becomes the second Marked One.
Grenzenlose Macht (Infinite Might) leads the characters to the ravaged city of Greifenfurt. They are hired by the monastery of Arras de Mott to investigate and prevent acts of sabotage that jeopardize the reconstruction of the monastery. Unknown to them, the head of the monks was replaced by a shapechanging demon that tries to build a portal to the Valley of Elements and a focus for magical energy. In the valley, Borbarad wants to create his new staff from Seelenstamm, a gigantic ancient tree. The attacks on the monastery are masterminded by Archon Megalon, a druid the characters may have encountered before and whom they will not remember with joy. After some events in the monastery, the arrival of the inquisition will force the characters to escape and enter the Valley of Elements, where they battle Borbarad's minions. They come back to Arras de Mott to destroy the astral focus. Here they meet the first time with the real Borbarad who bathes in the magical energy. The destruction of the astral focus delays Borbarad's plans, but also destroys the monastery, which is the end of this third adventure.