What happened in The Commuter? Timothy Spall's Electric Dreams episode explained

It stars Spall as an ordinary man named Ed Jacobson who works in a ticket office at the train station. One day a woman named Linda (Tuppence Middleton) turns up asking for a ticket to Macon Heights. When he tells her there is no such place, she vanishes in thin air. This sets him off on a mission to visit Macon Heights – with huge consequences.

The whole adventure leaves us with a ton of questions, so we've tried to answer them with the help of the original short story...

Why does Ed's son stop existing once he visits Macon Heights?

In the TV version, the mysterious Linda decides to remove Ed's mentally ill son Sam from his life for his own benefit, delivering Ed and his wife into an alternative timeline where they were never able to have kids.

At first Ed enjoys this alternative reality, and seems to forget he ever even had a son – but ultimately he realises his love for troubled Sam, begging Linda to give him back his old life despite everything.

What's going on here? Why did reality change once Ed visited Macon Heights?

Thorne's interpretation puts the power to change reality in the hands of Linda. She can't cure Sam of his problems, but she can stop him from ever having existed.

The whole idea comes from Philip K Dick's original story The Commuter – where the logic is somewhat different.

In the original, train station worker Paine goes to visit Macon Heights. When he returns to the city, a few things have changed – shops have popped up that were never there before. He realises that two alternative realities are colliding: the world in which Macon Heights was built seven years ago, and the world in which it wasn't.

As the realities merge, he has a moment of understanding: "It was spreading. Beyond Macon Heights. Into the city... Macon Heights couldn't exist without warping the city. They interlocked."

As the reality in which Macon Heights WAS built becomes firmer than the one in which it WASN'T, there are knock-on effects. Paine returns home to find he now has a baby daughter.

Why does Macon Height sort-of exist?

In the Electric Dreams episode, Macon Heights only seems to exist for people hand-selected by Linda. Journalist Martine Jenkins (Anne Reid) knows about it but can't visit, despite her attempts to investigate.

But miserable fathers, rape victims, paedophiles – Macon Heights is for them.

Martine's theory is that Macon Heights is not a town that "doesn't exist", but is a town "that almost existed – I think that's somehow different". The real Linda was the daughter of the developer who wanted to build the town, but he killed himself – and then she mysteriously disappeared.

Now Macon Heights is Linda's town, but it's a kind of weird, perfect, fake world where the same thing happens every day like clockwork. The implication is that Linda "fixes" people's lives (with or without their consent) and in return they must commute to her Macon Heights utopia.

In the original story, The Commuter is really about alternative timelines and the nature of the past.

The project to build Macon Heights was rejected by a single vote, meaning it was almost approved, but now Paine wonders: "Maybe certain parts of the past were unstable. Maybe that particular period, seven years ago, had been critical. Maybe it had never completely 'jelled'."

Now, that alternative timeline is taking over. Macon Heights is suddenly on the train map, and everyone says it has always existed.

Why does Ed's presence in Macon Heights damage the town?

When Ed arrives in Macon Heights to demand his old life back, people regard him with suspicion and the waitress says his presence is damaging the town.

Perhaps this is because he fights back against Linda's authoritarian view of a "perfect" life? It's not entirely clear.

Why does Ed's colleague Bob have kids?

Weirdly, when Ed returns to the city having had his life turned upside-down by Linda, he discovers that his childless colleague Bob Paine (Rudi Dharmalingam) is now an exasperated family man with three daughters.

There doesn't seem to be any logic to this: sure, Linda's changed Ed's life so that he never had a son, but why does that mean Bob had kids?

This may simply be Jack Thorne's nod to the original story and its "alternative timelines" plot. In Philip K Dick's telling, it is Bob who visits Macon Heights and comes home to find he has a baby daughter.

Electric Dreams continues on Sunday 8th October at 9pm on Channel 4 with Tony Grisoni's episode Sales Pitch