The lead characters are ex‑astronaut Jeff Tracy, founder of International Rescue, and his five adult sons, who pilot the organisation's primary vehicles: the Thunderbird machines.
In 1966, Century 21 released an audio adaptation of "End of the Road" on vinyl EP record (Thunderbird 2, catalogue number MA 109) with narration from voice actor David Graham as regular character Brains.
Although going to Eddie's aid presents a security risk, Jeff refuses to abandon the organisation's humanitarian principles and immediately dispatches Scott, Virgil and Alan in Thunderbirds 1 and 2.
Virgil and Alan lower Thunderbird 2's magnetic grabs and move in to pick up the truck, but are forced to back away when the craft's thrusters begin tipping it over.
[5] The puppet-scale set representing the truck's interior featured controls and seats previously seen in "Trapped in the Sky", "The Uninvited" and "Martian Invasion".
[7] Scenes from "End of the Road" appear as a flashback in the clip show episode "Security Hazard", which features a modified version of Eddie's truck as an International Rescue fire-fighting vehicle.
[8] Marcus Hearn acknowledges the episode's "relatively sophisticated emotional dilemmas", noting especially the "element of domestic tension" provided by the romantic rivalry between Alan, Tin-Tin and Eddie.
He adds that Alan and Tin-Tin's reconciliation – as well as International Rescue's commitment to saving Eddie, despite the risk to its security – shows that there is "no place for moral ambiguity or unhappy endings" in the series.
He suggests that Eddie and Bob Gray's "boardroom drama-style" confrontation was influenced by The Plane Makers, a drama series about power struggles among the staff of an aircraft factory.
[11] For Braxton, "End of the Road" is one of a number of episodes – also including "Pit of Peril" and "Path of Destruction" – which incorporate themes of "mechanisation despoiling the natural world".
Braxton also notes the episode's portrayal of the "destructive potential of workplace pressures", viewing this as a forerunner of the interpersonal conflicts depicted in the Andersons' live-action series UFO.