Tripp mistakenly believes the filming of a martian movie is a real life alien invasion. When a situation happens on set, no one believes Tripp this time around, and Roxette has to persuade Jeff to launch the Thunderbirds.
Brains and Tin-Tin travel to Lake Anasta to look for treasure, but the Hood turns up and sabotages the expedition. Making matters worse, Tripp is hypnotized - putting both the expedition and Hacker Command out of action.
Roxette finds herself taking care of two problems at once - shrinking alligators that have grown to ginormous size and restoring the shrinking Tripp to his former size.
Scott and a few hippy music-lovers get involved in a terrorist transaction with a tribe of aliens. Roxette is the only one that can see through the deal and try to stop it.
The Hood wire-taps London Tower in an attempt to sabotage the Red Arrow project. However, Roxette and Tripp are more focused on squabbling than saving the doomed project.
Tripp's April Fool's prank backfires, resulting in the destruction of "Ocean Pioneer King". To make things worth, the Atrocimator's fatal fog has penetrated Hacker Command.
An Aqua Institute yacht carrying an important government official is destroyed while Tripp was supposed to be monitoring it. Lady Penelope goes undercover to work out what happens.
Roxette and Tripp are surprised to see an International Rescue mission broadcast live on television. Upon discovering the photo alert has not sounded, they realize that the people on TV are not the real International Rescue.
Roxette and Tripp hold a party, but soon discover there is little to party about when the Hood blows up an oil rig and the Tracy family begin to slowly disappear.