Guardians of the Galaxy-1
The Asgardians Lady Sif and Volstagg entrusted one of the vastly powerful Infinity Stones, vastly ancient artifacts with the power to unmake worlds, to The Collector Taneleer Tivanm believing that two of the Stones remaining in Asgard would be too dangerous. With the Stone seemingly safe, the Asgardians returned to their realm. However, this only invoked a desire to gather the remaining Stones for his own purposes.
Others sought to find the Stones for themselves as well. The intergalactic conqueror known as Thanos also seeks the Stones, dispatching Ronan the Accuser and his Kree Empire to obtain the Stones for him, Ronan being outraged at the peace treaty signed between the Kree and the Xandarian Empire. He vowed to obtain the Stones for Thanos, in return for watching Xandar burn, sending his Kree armies to attack Xandarian outposts and settlements in his quest.
Of course, while this war rages, the galaxy is ripe for opportunists, and the most unlikely of guardians may surface...
The events of the movie have not happened in this theme. Additionally, as long as they don't interfere with what is seen in the movie, certain elements from the comics are integrated into this theme.
This theme is part of the Marvel Movieverse. Its "sister-theme", The Avengers-1, also exists on the MUSH. It was decided to separate the two for administrative purposes.