Years of research in the field of space physics gave one ambiguous result - it was possible to break a channel into the parallel world. However, nothing material can not be transferred into this world till now. Only foggy images in the thermal spectrum were shown.
It is because of poor visibility in the familiar spectrum that the world received the code name "Fog". It was possible to continue exploring the world thanks to the development of controlled robots consisting of force fields. These robots were named Misty Stalker, or simply Stalker. To accelerate research and expand the coverage of the study area, scientists have attracted volunteers, who are given a free module for a mobile device.
The main requirement is that the device must have a positioning module between borders of the planet. Creating a Misty Stalker requires a certain amount of energy, and low-power devices lose a lot of time for its accumulation. And its destruction is not a very complicated matter, anomalies and dangerous creatures constantly destring such robots.
However, the robot from the force fields has the ability to change - to capture the matter of the world "Fog" and strengthen its properties.