It's Grandma's birthday and Max and Ruby are having a party for her. Ruby has invited seven stuffed-toy guests she's sure Grandma will like. Max wants to invite his Jellyball Shooter Spider, his Ear-Splitter Space Cadet and his Can't-Sit-Up Slug, but Ruby says no. Yet each time Ruby counts the number of guests at the table, another one has mysteriously appeared. Is Ruby having a bad counting day? Or is someone making a few changes to the guest list?