It is raining hard on the Island of Sodor. Bill and Ben are up to there usual mischief: they splash George and tease Henry and BoCo. One day, a huge storm hits the Island and the docks are in total chaos. Bill and Ben bring China Clay to the docks and then head home, but not without teasing Edward and BoCo. As soon as the twins leave, James arrives with the workmen and complains about the weather. Suddenly, the flood siren goes off, and there is a huge flood coming towards the Brendam Peninsula. James immediately leaves while Edward and BoCo rush to help with the evacuation at the China Clay Works. With the help of Bill and Ben, all the workmen scramble into vans, coaches, and trucks. They then successfully evacuate the quarry, or so they think. Ben realizes they have forgotten the men in the mine shaft. After convincing Edward and BoCo to do so, they rush back to the China Clay works. They grab the men and hurry out. But the line is now almost submerged in water. Luckily, they get out of the area before a giant wave smashes down on the China Clay Works, drowning it in more than 10 feet of water. On the way to Wellsworth, the twins face many challenges, including crossing a bridge that is about to be swept away by the river. When it is, the twins have successfully crossed it. Eventually, the twins make it to Wellsworth and are congratulated. The flood has caused lots of damage but it is soon repaired, and the Fat Controller praises Bill and Ben for risking their lives to save the workmen.
- Bill and Ben
- Sir Topham Hatt
- Daisy (appears in flashback, does not speak)
- Bert (cameo)
- Derek (cameo)
- Donald or Douglas (cameo)
- Oliver (cameo)
- Old Slow Coach (cameo)
- Toad (cameo)
- Diesel (cameo)
- Diesel 10 (cameo)
- Duck (cameo)
- Percy (cameo)
- Thomas (mentioned)
- Toby (mentioned)
- Terence (original script only, replaced by George)
- Arlesdale Railway
- Lower Suddery
- Brendam Docks
- Center Island Quarry
- China Clay Works
- Rolf's Castle
- Bill and Ben: SamTheTrainFan
- Edward: EnterprisingEngine93
- Boco: Tommy Davias
- James: Andrew Homer
- Everyone Else: Thomas1Edward2Henry3
- The working title for the episode was "Fortis Gemini", which is Latin for "Brave Twins".
- This episode is the first to feature the second intro, as the first intro was complained to be too long.
- This is the only episode to feature the voice of CurtyLara2/SamTheTrainFan, not counting the recycled lines in How the Diesel Stole Christmas.
- This is the final episode to feature the voice of Tommy Davias. His channel was shut down due to copyright infringement afterward.
- A British Airways Boeing 747 can be seen flying by in the shot of George.
- George's role was originally Terrence's, but was swapped because it would be out of character for Terrence.
- This is the first to feature the Sudrian Community's 2010 model of Oliver.
- The Thomas and Friends episodes Thomas, Percy, and Old Slow Coach, Toby and the Flood, and The Sad Story of Henry are referenced.