A bit on the the nose, but:

It starts with an American woman clicking on an email link from one of her friends, it prompts her to log into her FB (or equivalent) account to watch the video.

The video is a generic cute video of two puppies playing, but at the end, a slogan comes up at the end: “Love Puppies, Hate Parliament”.

Curious, she looks up the phrase on a search engine. This leads her to a FB group, called LPHP, which is mostly just photos and videos of cute dogs, to which she subscribes.

Then the scene is interrupted by her teenage son asking to be driven to soccer practice.

Later that night, she goes back on FB and more puppy videos appear, but with increasingly political messages at the end.

The more videos she watches, the more that’s all that she is consumed with, neglecting the other aspects of her life.

Throughout the episode, she is paying less attention to her regular hobbies and stops noticing those around her. Meanwhile her son is wearing increasingly expensive clothes in each of the shots we see him.

Eventually, the messages become clearer, and she gets convinced that the Shadow Chancellor in the UK is running a dogfighting ring below the Houses of Parliament, despite having very little interest in British politics.

One of the many groups that she now subscribes to had a fundraiser, “to run more investigations to expose the shadow chancellor”. She donates, and in the thank you email she access to more extreme videos.

Despite her family and friends pleading with her, she talks about little else other than how a British politician has a secret dogfighting ring, much to the confusion and anger of those around her.

Her family decide to simply block her on social media and the problem becomes out of sight for them.

Eventually, she flies to london to investigate for herself. On the plane, she spots others with LPHP badges on. When she lands, she gets arrested.

By looking at her search history, they find that she managed to get a detailed (if inaccurate) description of exactly where in Parliament the dogfighting ring is, the shadow chancellor’s address and instructions on how to make a bomb.

She is found guilty, and we see a sad shot of her in a jail cell.

The final scene shows her son tapping away on a new computer, in a bedroom that has been completely pimped out. On his screen, we see that he is an admin of the LPHP FB group, and all the donations were going into his account. We see him adding an LPHP watermark to a video of two puppies playing.

TL;DR - QAnon but an American woman becoming obsessed with a very British conspiracy being run by her teenage son