After a fun weekend, Ned says he can't wait for the next one. This gives Newton the idea to build a time machine out of household items so that they can go back to Friday and do the weekend over again. They can't control the machine, however, and it ends up taking them to the Jurassic period, where Ned accidentally stomps on a fly and changes history, causing newts to be the dominant life form on Earth instead of humans. They go back and fix this change, but still have trouble controlling the time machine to take them home, causing them to end up at Gilligan's Island. However, it turns out to be a dream, but the trip to Gilligan's Island was proven to be real.