- "Look fellas, if that kid is roaming around the base on his own, dad's gonna go berserk!"
— Scott Tracy
While Thunderbird 2 is left unattended at a rescue, a young boy named Chip climbs into the pod and is taken back to Tracy Island. As Jeff tries to decide what to do with their stowaway, the boys entertain him with stories of their past rescues, thereby exacerbating the breach of security that has already taken place.
- Main article: Security Hazard/Storyline
- Main article: Security Hazard/Transcript
- Jeff Tracy - Peter Dyneley
- Scott Tracy - Shane Rimmer
- Lady Penelope Creighton-Ward - Sylvia Anderson (Day Of Disaster flashback)
- Virgil Tracy - David Holliday
- Alan Tracy - Matt Zimmerman
- Brains - David Graham
- Tin-Tin Kyrano - Christine Finn (Sun Probe flashback)
- Gordon Tracy - David Graham
- Commander Norman - Peter Dyneley (Trapped in the Sky flashback)
- Captain Hanson - David Graham (Trapped in the Sky flashback)
- Fireflash Co-Pilot - Ray Barrett (Trapped in the Sky flashback)
- Chip Morrison - Christine Finn
- Morrison - David Graham
- Eddie Houseman - Ray Barrett (End Of The Road flashback)
- Bob Gray - David Graham (End of the Road flashback)
- J. B. Lester - Ray Barrett (End of the Road flashback)
- Colonel Harris - Ray Barrett (Sun Probe flashback)
- Solarnaut Asher - David Graham (Sun Probe flashback)
- Solarnaut Camp - John Tate (Sun Probe flashback)
- Assistant Controller - Ray Barrett (Trapped in the Sky flashback)
- Operator Harris - Ray Barrett (Trapped in the Sky flashback)
- Crash Tenders Chief (voice only) - David Graham (Trapped in the Sky flashback)
- Bill Craddock - Matt Zimmerman (Day Of Disaster flashback)
- Frank - David Graham (Day of Disaster flashback)
- Allington Suspension Bridge Controller - Ray Barrett (Day of Disaster flashback)
- Dave Clayton - David Graham (Day of Disaster flashback)
International Rescue Equipment UsedEdit
- Thunderbird 1
- Thunderbird 2 (Pods 1, 2, 3 & 4)
- Fire Truck
- Mobile Control Vehicle
- Thunderbird 3 (Sun Probe flashback)
- Thunderbird 4 (Day of Disaster flashback)
- FAB 1 (Day of Disaster flashback)
- Elevator Cars (Trapped in the Sky flashback)
- Electromagnetic Pod Grabs (End of the Road flashback)
Non-International Rescue Equipment UsedEdit
- Commercial Fire Trucks
- Fireflash (Trapped in the Sky flashback)
- Gray & Houseman Road Construction Vehicle (End of the Road flashback)
- Gray & Houseman Explosives Truck (End of the Road flashback)
- Sun Probe (spaceship) (Sun Probe flashback)
- Martian Space Probe (Day of Disaster flashback)
- Floating Cranes (Day of Disaster flashback)
- This episode was essentially a clip show, with roughly seventeen minutes of new footage spliced in between the original scenes. This is hardly a new practice, as nearly every Anderson-produced series had at least one clip show in its run, both before and after Thunderbirds.
- This is the only episode where Pod 2 is used.
- Clips from the following episodes were used:
- Smoke can be seen flowing backwards as Thunderbird 2 reverses into its hangar.
- Once back inside the hangar, Thunderbird 2 unloads Pod 1, but the numeral on the puppet sized pod door in the close-up shots does not match that in the model scale long shot.
- The Globe in Chip Morrison's bedroom is upside down.
- Not a goof per se, but Alan sure is quick to conveniently forget mentioning Thunderbird 3 nearly plummeted into the Sun after saving Sun Probe.
- Plus Virgil 'forgets' to mention that in his flashback, Eddie almost died when Thunderbird 2's lifting equipment lost its grip on his truck.
- And again, Scott appears oblivious to the fact there were two attempts to land Fireflash on the Elevator Cars.
- It is most likely that the flashbacks were shortened so more time could be spent on filming the newly filmed scenes instead of showing the whole flashbacks.
For a contemporary (or at least in the 1990's) audience, Thunderbirds underwent a repackage, redub, and rebroadcast as part of FOX Kids' Saturday morning line-up. Due to a severe decline in ratings, only half of the episodes made it to broadcast before the series was pulled by the network. As a result, the modified version of Security Hazard never aired, and remains among a handful of missing Thunderbirds episodes to this day.
- French: Le rêve
- German: Das Sicherheitsrisiko
- Spanish: Peligro de Seguridad; Riesgo de seguridad (DVD)
- Italian: Una visita inaspettata
- Dutch: Veiligheidsrisico
- Japanese: 秘密作戦命令