Cobweb ending explained: Director unpacks the final scene

His parents (played by Antony Starr and Lizzy Caplan) insist that this is only happening in his imagination - however, slowly but surely, a sinister secret begins to emerge that puts Peter in grave danger.

The film's script – which was written by Chris Thomas Devlin – was one of many sent to French director Samuel Bodin while he was looking for his first English-language project, and speaking exclusively to RadioTimes.com, he explained how it instantly grabbed him.

"I read Chris's script and something struck me," he revealed. "It was how simple it was... With a strong universe and a really twisted, acid thing in it. And I thought, 'Oh, my God, I have something to tell with that.'"

It all eventually leads up to a chilling finale – and we spoke to Bodin about what those final scenes really mean. Read on for everything you need to know.

Cobweb ending explained: director unpacks the final scene

Towards the start of Cobweb, Peter hears a tapping from his bedroom wall and begins to talk with a mysterious entity who tells him that her name is Sarah and that Peter's "evil" parents had trapped her in the walls.

For much of the film, it is left unclear whether Peter is really talking to a voice in the walls or if everything is simply happening in his imagination – and Bodin said that keeping this ambiguous was not always an easy task.

"It was a tricky question," he said. "Because the script was simple, in a good way, [but] to know where the audience is during the story is another question.

"And in each sequence, we had to say, okay, the character trusts that, and we want the audience to trust that. And we have to be honest with ourselves – do they trust that or do they need help from us?

"And so it was a kind of a game. We worked a lot in preparation with the actors, with Chris, and with the crew to say, 'Okay, if they already know, I have to hide it more."

Of course, it eventually transpires that Sarah is real – she was Peter's older sister who had been locked away due to her monstrous appearance, and their parents were so desperate to keep her existence secret that they had even killed a girl who saw her when she escaped one Halloween.

Peter is convinced by Sarah to kill his parents by slipping them rat poison, but afterwards it emerges that she is not really on his side either – and she emerges from her prison desperate to kill him, too, jealous that he has been able to live a comparatively normal life.

After a bloodbath that sees all of Peter's bullies – who had arrived at his home to give him a beating – killed by Sarah, he is eventually able to escape with the help of his sympathetic school teacher Miss Devine (Cleopatra Coleman).

In the final scene, Peter is seen to have been adopted by Devine and appears to finally be safe – only for Sarah to suddenly appear from nowhere and taunt him.

This time it really is unclear whether she is actually there or if it is simply Peter's imagination, haunted by everything that has happened.

"It's a chilling moment," Bodin said. "And maybe it's a moment that's too fast. But what we wanted to do was create something... like a trope in the movie is what's in your imagination, and the audience knows that it's not his imagination.

"But when you put something in your mind it can eat you all your life, and that's the idea, is that from now on you won't be okay whatever you do.

"And she says to him, 'You are a killer, too.' And that's a fact, you know? So the question is, oh, maybe they have something in common, you know? So at the end, you say, 'Okay, there is something twisted in him, too.'"

Will there be a Cobweb 2?

Given Sarah's reappearance at the end, you might wonder if there's scope for a sequel – and Bodin has said that, while it was planned as a one-off, he couldn't rule out a follow-up.

"For my path, as a director, I really took the story as a standalone," he explained. "But I'm sure... you know, you always say that, and suddenly someone has a great idea.

"And if the idea is great, there is a story... it's the right thing to go, 'Okay, now we have something else to tell. So, you know, let's do it.'"

He added that any future film could possibly even take the form of a prequel rather than a sequel.

"Maybe, you know, we could imagine what happened before... because there are a lot of things to imagine," he said. "So why not?"

Cobweb is now showing in UK cinemas. Check out more of our Film coverage, or visit our TV Guide and Streaming Guide to find out what's on.

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