After the player's partner summons the Rainbow Stoneship, Dusknoir opens up a portal back to the future, intending to take all four characters with him; however, Grovyle, mustering his strength, pushes him back into it, so that only the two of them return. Grovyle then says goodbye to the player and the partner in the present, giving the pair all five Time Gears they need, and with his last bit of energy, pushes both Dusknoir and himself into the portal and thus into the future; they are deposited at the entrance to this dungeon. After some bickering and arguing between the two, Grovyle leaves Dusknoir behind to explore the dungeon alone; however, Dusknoir follows him inside.
There are ten floors total - five in Barren Valley and five in Deep Barren Valley, with a waypoint between the two (after the fifth floor but before the sixth). At the end of the dungeon is the Barren Valley Clearing, where Dusknoir catches up to Grovyle before the duo are ambushed by four of Dusknoir's servants, Sableye. It is after this battle that Grovyle and Dusknoir call for a truce and journey together.
When Grovyle travels through the valley and deeper into the time-frozen place, the number of traps that can be encountered at a time starting from the first floor to the third is 7, and then 8 from the fourth floor and the remainder of the valley. There are no traps or Wonder Tiles in the sixth floor.