Mysteries is the forty-second episode from Hi-5 Series 5.
- NATHAN plays with different sort of sponges.
- CHARLI pretends to be a sponge.
- KATHLEEN's jelly beans are disappearing, so she finds a thumbprint on the jelly bean jar and investigates the mystery.
- CHARLI searches for something important.
- TIM teaches some ants (Charli, Nathan and Kellie) the lyrics of It's A Party song.
- CHARLI pretends to be a giant.
- KELLIE gets a package that sounds cheep cheep and she tries to guess what's inside it.
- Kellie gave CHARLI two boxes and she guesses what's inside them.
- SHARING STORIES: Tim tells us a story about a royal family (Kathleen and Charli the princesses and Kellie the queen), Kathleen and Kellie love singing loudly but Charli doesn't, and once a dragon (Nathan) arrives to the castle and gets a headache because of loud singing.
- During Kathleen's segment and second Charli's segment, they wore the same costumes from Rain Rain Go Away.