"Heavy Metal" is the 13th episode of Thunderbirds Are Go!. It was first broadcast on Saturday June 20th, 2015.
Alan flies Brains to the Quantum Research Center in Switzerland, where the Supreme Hadron Collider is housed. There, they meet Brains’ old University friend, Professor "Moffie" Moffat who Brains has a crush on. She demonstrates the operation by activating the collider and Alan starts the atomic collision. Up on Thunderbird 5, John glimpses an unknown meteorite falling through Earth’s atmosphere and heading straight for Switzerland. He tells International Rescue that the meteorite has crashed in downtown New Geneva. Virgil lands there in Thunderbird 2 and finds out that the meteorite was a satellite. Alan thinks the Hood brought it down. Suddenly, a plane passing over Switzerland descends uncontrollably and Scott heads out in Thunderbird 1 to save it.
Scott tries to pull the jet out of its dive but Thunderbird 1 starts to fly out of control. Brains says that there was no sign of sabotage. After Alan thinks the plane is dragging Thunderbird 1 down, Brains says that the plane is a Botchley Skyliner with a crew weight of 318.7 metric tons. He then explains that Thunderbird 1 is in an inclined dive of 6.7G but with a vertical thrust of 470 000 pounds which is enough to pull 6.4 Skyliners. They guess that gravity here isn’t normal and John runs a gravity scan on Thunderbird 1. Brains tells Scott that he is caught in a gravity well. Alan thinks gravity can make him go faster and tells Scott to accelerate to 9Gs to get out of the gravity well and Thunderbird 1 and the plane safely manage to avoid crashing.
Back at the Quantum Research Centre, Moffie tells Brains and Alan that they have been scanning localized gravitational anomalies when the Supreme Hadron Collider went online. Brains explains that the collider had the right conditions to generate the gravity well when it was activated. They try to shut it down but the gravity well is still active and self-sustaining, pulling the Worldwide Space Station out of orbit. As everything in the control room goes weightless, Brains says that they need to stop the collider physically. He explains that the process would require Thunderbird 4 with its compact pressurized structure.
Virgil and Gordon arrive with Thunderbird 4 and safely fly into the heart of the gravity well where Gordon is lowered into the collider's chamber. Thunderbird 2 gets caught in the gravity well and Alan takes off in the Helipod to help Virgil. As Alan struggles to get higher, Scott arrives in Thunderbird 1 to help. After several plans to shut down the collider, Gordon destroys it with Thunderbird 4's demolition missiles, causing the gravity well to dissipate. As the Tracy brothers touch down, Gordon says that he was about to get squashed and Alan jokes that he has gotten a bit shorter. When Moffie says that the collider is destroyed, Brains says that it can be rebuilt better than before and she kisses him on the cheek.
- Brains: Kayvan Novak
- Scott Tracy & Alan Tracy: Rasmus Hardiker
- Virgil Tracy & Gordon Tracy: David Menkin
- John Tracy: Thomas Brodie Sangster
- Professor Moffat: Teresa Gallagher
- Note: the following section is large. As such, it is hidden by default.
- Special thanks to: Elaine Kelman
- Voice director: Dave Peacock
- Original dialogue record: Simon Capes, Soho Squares Studios
- Miniatures: WETA Workshop
- Design & miniature FX supervisor: Richard Taylor
- Lead model maker: Steven Saunders
- Workshop supervisor: Rob Gillies
- Production co-ordinator: Holly Beals
- Model makers: Sofia Pedersen, Mona Peters, David Duke, Joaquin Loyzaga, Laura Marie King, Abigail Smith, Masayuki Ohashi, Pietro Marson, Sourisak Chanpaseuth, Kim McAuslan
- Director of photography: Simon Godsiff
- 1st assistant director: Robin Wilson
- Production manager: Sadie Wilson
- Gaffer: Simon Oliver
- 1st assistant camera: Charles Edwards
- Key grip: Jan Kleinheins
- On set model technicians: Rob Chesney, Ben Fairless
- Lighting equipment: Portsmouth Lighting, NZFX SFX Equipment
- Catering: Deborah Logan
- Production designer: Ben Milsom
- Designer, Thunderbird Shadow: Shoji Kawamori
- Lead concept artist: Christian Pearce
- Concept artists: Aaron Beck, Gus Hunter, Rebekah Tisch
- Head of design: Richard Athorne
- Design studio co-ordinators: Tasha Guillot, Catherine Mitchell
- Asset supervisor: Sven Trotter
- CG modellers: Ben Hutchinson, Tom Robinson, Ben Picking, Che Thorpe
- 3D story supervisor: Tim Gaul
- Lead 3D story artists: Martin Haughey, Andrew McCully
- Matchmove: James Donald, Luke Swasbrook
- 3D story: Jason Campbell, Eduardo Gutierrez, Rhys Hanan, Nagaraju Kusama, Kai Ma, Ben van de Laar, Robin Wilson-Davey
- Head of production: Sareana Sun
- Production executives: Ivan C, Alen Fang, Andy Tsao
- Production team: Sean Li, Lara Lin, Jing Zhang, Yao-Cheng Wang, Heyifang, Tan Tao, Xu Ding, Shiwei Yang, Aimee Zhang, Zhenhua Yao, Xuren Chen, Shamy Lai, Wei Lin
- Editor: Anthony Cox
- Assistant editors: Louise Pattinson, Adam Reynolds
- 3D artist: Rhys Clapcott
- Software engineer: Mike King
- Animation supervisor: Chad Moffitt
- CG supervisor: Andrew Harris
- Data wranglers: Joyce Kamille Cristal, Wattana Moeung, Clare Brody, Park Road Post Production
- Casting: Peacock Sound
- VFX line producer: Malcolm Angell
- Production co-ordinator: Sophie Gregory
- Production assistants: Brittany Connell, Jordan Harding
- Production secretary: Christine Healy
- Production runner: Nate Hinde
- Script co-ordinator: Patrick Rieger
- Post production co-ordinator: Dee Collier
- Legal and business affairs: Sally Perry, Sarah Cull
- Production accountants: Emily Stafford, Karen Kong
- Special advisor, International Rescue: David Tremont
- Branding and title design: ITV Creative
- Compositing: Milk VFX
- Online editor: Simon Brook
- Colourist: Paul Staples
- Picture post production: Encore London
- Sound effects editor: Darren Banks
- ADR Recordist:Alexander Fielding
- Foley engineer: Keith Partridge
- Mix technician: Kiran Marshall
- Audio post production: Jules Zabbar
- Music composed by: Ben Foster, Nick Foster
- Original theme: Barry Gray
- Sound designer & re-recording mixer: Nigel Heath
- Audio post-production: Hackenbacker
- Producers: Sharon Lark, Stuart McAra
- Line & consulting animation producer: Teresa Reed
- CITV commissioning editor: Jamila Metran
- Executive producers: Estelle Hughes, Giles Ridge, Andrew Smith, Richard Taylor
- Based on the original series by: Gerry & Sylvia Anderson
Brains: "Quantum Research Center. Home of the Supreme Hadron Collider. It's like a g-giant theme park of science."
Alan: "Cool! Where are the rides?"
Professor Moffat: "Hiram!" (approaches and hugs Brains)
Brains: "Nice to see you again, Moffie."
Alan: "Looks like someone just spun your bosens."
Brains: "Something must have caused it to fall out of orbit."
Alan: "Something, or someone. I'm calling sabotage. And if you look up sabotage in the dictionary, you'll find a picture of The Hood."
Alan: "Thunderbird 1, accelerate to 9G's."
Scott: "In an incline dive, are you crazy?"
Alan: "Trust me. I've done this before. Of course that was in space and I wasn't towing a jet plane, but..."
Scott: "FAB, I guess."
Brains: "But the idea of a graviton generator inducing a gravity well is only a theory."
Alan: "Alright, imagine for a second that we all don't have PhD's in particle physics."
Brains: "I find at moments like this it's best to recite my fractal tables."
Professor Moffat: "You're such a nerd, and I like it."
Gordon: "Boy, I'm glad that's over. I thought I was going to be squashed."
Alan: "Now that you mentioned it, you do look a little shorter."
International Rescue Equipment Used
Non-International Rescue Equipment Used
- Supreme Hadron Collider
- Botchley Skyliner
- GDF Satellite
- Worldwide Space Station
- This is the final episode of Season 1's first half to air.
- This episode marks the first time Thunderbird 4 has been used for a rescue mission not underwater.
- The Supreme Hadron Collider is a direct homage to the Large Hadron Collider in Switzerland at CERN.
- Dr. Moffat refers to Brains as Hiram, suggesting that the alias Brains used in Alias Mr. Hackenbacker is his real name in this incarnation.
- Captain Lee Taylor, or someone strongly resembling him, can be seen aboard the Worldwide Space Station.
- No-one is credited for voicing the jet plane pilot nor the female astronaut aboard the Worldwide Space Station in this episode.
- Dutch: Zwaartekracht (Gravity)
- French: Métaux lourds
- Spanish: Metal Pesado
- Japanese: 重力の井戸 (Well of Gravity)
- Arabic: معدن ثقيل