Whistle For Danger is the 31st produced episode and the 28th Broadcast episode of the series Fireball XL5
The crew of the XL5 are sent to the planet Floran to explode an Ellvium bomb in the atmosphere to kill Planitoid Three, a plant disease, so that plant life can be restored. When the bomb is exploded, two Florans manage to drug the crew and imprison them in a tower. When they try to use a tall plant as an escape route, the Florans realize that they have come to help and are able to save the crew from what is actually a man-eating plant.
- The picture of Floran on the monitor in the conference room at the start of the episode shows that the footage of Floran was shot in January 2063, meaning that this episode must take place after Trial By Robot.