When a bottle of ketchup explodes all over Masha Sweet, she thinks it's an accident. She's trying to be kinder to her little sister, Sunny so she shouldn't jump to conclusions...or should she?
Turns out Sunny has devised a special science experiment that requires Masha to look totally weird all day. But Masha is not having it. If it kills her (or Sunny!) she will figure out how to get them home from the science fair without causing a scene. But add in a pair of little brothers who take Masha on a wild goose chase through the school, a short detour through a cemetery, and a run-in with a cute boy and this whole day is one big scene. Which just might be what Sunny had in mind...she is so dead meat!