The Heart of Britain train from Glasgow to London was “hack-jacked” and no one knows exactly why. This happened just after a big anti-virus software got a virus. Nothing is certain in this new world of technology.

The passengers on the train have no internet or cell service. The only connection to the outside world is the one satellite phone that happens to be on board. The owner, an oil rigger, reluctantly hands it over to the lone police officer on the train, who then contacts the government agency in charge of cyber security.

Joe (Joe Cole) is a former police officer who was accused of a crime but never convicted as he took off before he could be prosecuted. He is the one person on the train who has some training to deal with the situation.

Abby (Alexandra Roach) is the person tasked to handle this situation in the cyber security department and who, along with her colleagues, are tech gurus. Joe and Abby must work together to stop the train that is being run remotely by an unknown “driver.”

The train manages its first stop. However, not all the passengers make it off before “the driver” remotely locks all the doors and starts the engine. As The Heart of Britain rolls away, those on board are at a loss as to what is happening.

This is a tense thriller that looks at the complex state of technology in today’s world. It also looks at people’s reactions to the situation in which they unwittingly become entangled. Viewers will undoubtedly get upset by some of the selfish people who are dealing with their own lives while at the same time being pawns in this international drama.

The handful of passengers are understandably panicked by the situation. However, there might be someone on board who is connected with the “hack-jacking.” But who could it be? This could be a great additional story for the board game “Clue.”

While the train rolls down the tracks, another problem facing Abby is the fact that the Internet is down which means the software that shows exactly where every train is, is down. The officials are blind when it comes to tracking the trains, therefore, although all trains have been ordered to stop where they are, some trains might be in the path of The Heart of Britain.

As this intense and tense situation develops over the six episodes, the dilemma becomes international as France is brought into the mix. In this world where companies are connected to several countries, the situation of The Heart of Britain is one example of how countries can be brought to their knees. It is also a wake-up call to having other countries invest heavily in major companies in other countries. This global world can be a blessing however it can also be a curse.

“Nightsleeper” is a throwback to the disaster movies of the late 20th century (“The Poseidon Adventure,” “Airport”, and “The Towering Inferno”) that started the modern genre. As the train travels on, the source of the tragedy is unknown until the final few minutes.

With a variety of personalities on and off the train, the situation evolves into instances of chaos, however the technology is the main dilemma. Personal conflicts invade both the group on the train and those in the cyber security office. It all comes down to Abby and Joe to bring this to a conclusion, and hopefully save lives.

All six episodes of “Nightsleeper” are available to stream on BritBox. The channel is available online, as an app for smart TVs, and an add-on to a Prime Video membership.