For as long as Xia can remember, it's only been her and her dad. That's because her mom passed away from an incurable disease just a few years after she was born. So, in his grief, her dad removed all pictures of her mom from their home and devoted the rest of his years to building a time machine. Lucky for Xia, it worked! Now 20 years in the past, Xia is determined to save her mom. Her next problem? She has no idea what her mom even looks like!