Goosebumps meets Stranger Things in book 6 of the FrightVision series: The Attack of the Yellow Smart Sack. Sometimes you own a backpack, and sometimes the backpack owns you! Lewis Izinger desperately wants a Yellow Smart Sack. Only the coolest kids at Cantaloupe Valley Middle School are carrying one. Not to mention the features. The Yellow Smart Sack is light as air, no matter how much it's carrying! Nothing ever gets jumbled...