Popstar Sam 7 is playing at the theatre and it's up to Jubilee to get him there.
Ernie dresses up in a suit of armour and gets stuck, before saving a maiden in distress.
Ernie has a bad cold so he leaves Millie in charge of Mr Rails's surprise party plans
The trains are excited to see their old friend Brooklyn, and US athlete Rocky Two Shoes.
Pippa's cat Patch disappears during a thunderstorm, and there are other strange goings-on.
A horticulturist brings a rare plant to the Underground that turns hands purple.
The trains are excited about the arrival of champion ice skaters Sasha and Natasha.