Year 2000 (MM) was a leap year of the Gregorian calendar that started on a Saturday. It was a century leap year. In some countries such as the UK, they claim it as the 3rd millennium, but the US denied this until 2001. After Hooky and Mermaid Man and Barnacle Boy II premiered on April 8, 2000, no new episodes aired until October. This also happened in 2004. This will be the second and last time there were episodes in December until 2012, when It's a SpongeBob Christmas! premiered.