Filming took place in a rail tunnel specially constructed within a giant event space in Changi Exhibition Centre, housing two actual, decommissioned MRT train carriages.
Apart from being the series title, third rail also refers to the part of the rail track that supplies a huge amount of electricity to the train, and is also a term for a politically charged issue.
Rebecca Lim may be more of a familar face in Mandarin television dramas in Singapore, but her acting debut was in the local English language drama series The Pupil (2010).
While the series is not inspired by any real-life train hijacking which had taken place in Singapore, the last high-profile hijacking which has a Singaporean connection and taking place in Singapore itself involved the national carrier Singapore Airlines flight SQ 117 on 26 March 1991 where a usual 50-minute flight from Malaysia's capital Kuala Lumpur to Singapore would come to be hijacked by Pakistani nationals, and also being retold in SQ117 Hijack (2015). Except for the hijackers, there was no casualties at all from the flight, earning praise and accolades from the international media for how Singapore handled the entire situation.