In the beginning, there was a wizard (who wore two magical gloves that could move on their own) throwing random bottles of liquid into a cauldron. He mixed the wrong potions and they made a big explosion, forcing the wizard to fall through the floor and turn into a fountain. As he fell, the wizard's two gloves fell off his hands and one fell into the cauldron while the other flew out the window of the castle. The glove that flew out the window is Glover. He saw that the crystals that kept Glover's world at bay were flying in random directions. Glover used his magic to turn them into balls and keep them from breaking. Each of the balls bounced through different portals to different worlds. Meanwhile, the glove that fell into the cauldron become corrupted from the fusion with the potions and emerged as Cross-Stitch, the game's main antagonist. Glover then starts off to recover all of the missing crystals.
In Glover, you must recover all of the missing crystals by going into each world and guiding them through three levels and a boss. Glover can push, toss, hit, or even run on top of the ball to guide it. Glover can use his magic to change the crystal into many forms: a round rubber ball, a small, metal ball, a bowling ball, or its original crystal form by pressing Z. Glover also finds various potions throughout the game that make him stronger, bigger, faster, etc. Glover can die in many ways. He can actually physically die, the ball/crystal can get hit three times, or Glover or the ball/crystal can fall off a ledge. Glover can also locate where Garibs (things to collect) and the ball/crystal is.