What on Earth?

SINOPSIS

The departure of Leonardo hits Zachary even harder. Just then, he heard a strange beeping sound coming from Leonardo's desk and found a mysterious cube-like device. Leonardo left Zachary a Zetabian puzzle box as a gift. Meanwhile, it's Neela's first day at school and she's already hating it. Turns out she is still upset that Uncle Maxie chose Leonardo to return back to Zetabia instead of her.