Continuity mistake: When The Hood drives his van off the broken bridge whilst escaping the police, watch carefully; the van bounces off the rocks on the other side and starts to fall roof-first into the river below. However, when it cuts to the van falling into the water it falls in upright. (00:42:00)
Continuity mistake: When Thunderbird 2 leaves the hangar on Tracy Island, it appears that Pod 3 has been selected (Pod 2 is visible to the right of Thunderbird 2), yet when Virgil and Brains arrive at Mount Arkan, the Transmitter Truck emerges from Pod 6. (The same continuity error also occurs in the episodes 'Vault Of Death', 'Move - And You're Dead', 'Martian Invasion', 'The Perils Of Penelope' and 'Day Of Disaster', probably due to the same footage being re-used for those episodes).
Factual error: An edition of the 'Melbourne Herald' newspaper can be seen in this episode, and appears to be dated Friday, December 24, 1964. Yet 'Thunderbirds' is supposed to be set in the 21st Century (2026 or 2065, depending on who you believe). This date is also seen on newspapers which appear in the episodes 'Edge Of Impact', 'The Impostors' and 'Cry Wolf'. Also, to compound the error, December 24th, 1964 was actually a Thursday, not a Friday.
Continuity mistake: Near the end of the episode, Jeff activates Operation Cover-Up to change the wall-mounted pictures of the International Rescue members from the usual pictures of them in their uniforms to ones of them in casual clothing before a doctor who has just examined Kyrano enters the room. However, while he and Jeff are talking, a couple of shots of Scott and Gordon contain enough of the pictures to show that they have reverted back the ones of them in uniform. (00:48:35)
Continuity mistake: When the shaft that Virgil slides down connects to Thunderbird 2, we can see Pod 3 to the right of Thunderbird 2. Seconds after Virgil's chair has locked into place, we see the pods slide across from left to right, including Pod 3. I thought that was to the right of TB2? It couldn't have been quickly moved to the left, as we see that Pod transportation is very slow. It couldn't of been a spare, as there is no sign of it when we see Pod 1, etc, roll to the right.
Continuity mistake: When Virgil radios to Jeff that he is about to land on Mount Arkon, Jeff asks him what the weather's like, to which Virgil replies: "Pretty stormy, Father. Pretty stormy." Then we cut to an exterior of the airborne Thunderbird 2, which is absolutely covered in snow. Just moments later we get a long shot and suddenly Thunderbird 2 is no longer covered in snow. We then get a close-up of the cockpit view, where we see Virgil and Brains, and Thunderbird 2 is covered in snow again. We soon get another couple of shots where it alternates between Thunderbird 2 not snow-covered and then being covered in snow again. (00:28:00)