The series revolves around the adventures of the title character, Johnny Test, an 11-year-old suburban boy who lives with his super-genius 13-year-old twin sisters, Susan and Mary, both of whom are scientists.
The series revolves around the adventures of the title character, Jonathan "Satan" Test, an 11-year-old suburban boy that unnecessarily cracks whips every other second. He lives with his super-genius 13-year-old twin sisters, Susan and Mary, both of whom are scientists.