International Rescue faces their most dangerous mission ever when Tracy Island comes under attack.
- Scott Tracy, Alan Tracy - Rasmus Hardiker
- Virgil Tracy, Gordon Tracy - David Menkin
- John Tracy - Thomas Brodie-Sangster
- Kayo - Angel Coulby
- Brains - Kayvan Novak
- Grandma Tracy - Sandra Dickinson
- Lady Penelope Creighton-Ward - Rosamund Pike
- Parker - David Graham
- The Mechanic - Chris Jarman
- Havoc - Aimee-Ffion Edwards
- Fuse - Craig Stein
Brains: "The m-music is a bit much, MAX."
[MAX turns off the music.]
Alan: "Hey, I kinda like it. Makes me feel like a real astronaut."
Scott: "Alan, you are a real astronaut."
Alan: "Oh, yeah."
Alan: "Ladies and gentlemen, welcome aboard the Zero-XL. This is your pilot, Alan Tracy speaking. Any questions?"
Gordon: "Is there a movie on this flight?"
Brains: "If we have any p-problems with the launch, we may end up a f-fireball."
Scott: "If we don't launch now, we're definitely going to end up a fireball."
Alan: "Going for throttle up, maximum power!"
Scott: "That was quite a ride."
Gordon: "Aside from regretting those tacos I had for lunch, yeah, I'm okay."
Jeff: "I've got you, son. Now, what do you say we get out of here?"
International Rescue Equipment Used
- Thunderbird 1
- Thunderbird 2 (Module 6)
- Thunderbird 3
- Thunderbird 4
- Thunderbird 5
- Thunderbird Shadow
- FAB 1
Non-International Rescue Equipment Used
- This is the first time that John is seen onboard Thunderbird 2, and he assumes the role of co-pilot.
- He was previously seen entering Thunderbird 2 during the episode Home on the Range, but the craft wasn't able to go anywhere.
- Scott and Brains both state that the Zero-XL will turn into "Fireball" if they don't lift off - a reference to Gerry Anderson's Fireball XL5.
- This is the first episode to feature Jeff Tracy in the flesh in person. Additionally, this was the first episode to feature Jeff's face. Jeff previously appeared through archive footage which was shown during the episode Signals Part 1, and his face was obscured by an opaque helmet.
- This is the first time that Thunderbird 1 is seen flying in space.
- This is also the first time that Thunderbird 2 is seen flying in space without modifications. It was previously sent into space, but it went under heavy modifications.
- Thunderbird 4 is also operated in the vacuum of space. Previously, Thunderbird 4 went on an aquatic mission in Europa.
- Also, Gordon once asked Brains (in jest) if he could make Thunderbird 4 into a spaceship.
- The Hood makes a silent cameo in this episode, having sneaked himself aboard the Zero-XL.
- At the very start of the episode, Alan learns that he has graduated from high school. This is a reference to his education in Runaway.
- Grandma Tracy states that to the Mechanic that they “don’t get to choose who to rescue” when the Chaos Crew disappeared into the ocean. This is a reference to Brains vs. Brawn where International Rescue were forced to rescue the Hood.
- When Parker uses Scott's travel tube to get down to Brains' lab for safety, Scott's uniform is in its usual place. But, Scott himself, having taken off aboard the Zero-XL beforehand, is already wearing his uniform.
- When Jeff's face is shown, it is seen through his helmet. However, when Jeff went missing (shown in Signals Part 1), his helmet had an opaque visor.
- This was probably intended by the writers to prevent showing Jeff's face in the flashback footage and to give a satisfying end to this episode. However, in-universe, it is a goof.