Now that the heatwave is over, we're embracing any excuse to stay inside and enjoy the slightly cooler weather, and that means one thing only - movie night! Gather the popcorn, order a pizza and get cosy on the sofa to watch a thrilling film. But if you're wondering what to watch and want to save half an hour debating which movie to stick on, we have the ultimate weekend watch.

My Son is the heartbreaking and intense thriller about a set of parents who discover their child has been kidnapped, starring British acting legends James McAvoy and Claire Foy. Not only is the plot gripping but it also features a unique acting experiment for McAvoy.

Curious to know more? Here's everything to know about the movie and how you can watch it for free this weekend.

london, england february 16: james mcavoy attends the 2025 ee bafta film awards at the royal festival hall on february 16, 2025 in london, england. (photo by kate green/getty images)pinterest
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What is My Son about?

My Son is a 2021 movie and remake of a 2017 French movie. It stars James McAvoy as Edmond Murray and Claire Foy as Joan, a pair of divorced parents who are frantically trying to find their missing son Ethan. However, in a unique experiment the movie saw McAvoy do the majority of the movie without a script and instead improvised the majority of the scenes.

Since the movie was released five years ago it's been highly praised by viewers on IMDb, with one person saying: "James McAvoy is a great actor, and to do this movie without a script? I say bravo!" While another said: "Beautiful scenery, I found this a tense and realistic watch." And another said: "The pacing of the movie is great. 90 minutes that fly in front of your eyes. The two first thirds build a great amount of distress and thrilling despair. The third act has more suspense and its bleaker touch."

Ok we're sold!

Who stars in My Son?

Leading the cast of My Son are James McAvoy and Claire Foy. McAvoy is best known for his performances in movies such as Atonement, X-Men, Split and The Chronicles of Narnia. You'll most likely recognise Foy from her role as Queen Elizabeth II in The Crown, and for starring in movies including All of Strangers, The Magic Faraway Tree, and H is for Hawk.

Also starring in the series is:

  • Tom Cullen as Frank Gilchrist, Joan's new partner.
  • Gary Lewis as Inspector Roy, the police inspector in charge of the search for Ethan.
  • Max Wilson as Ethan Murray, Joan and Edmond's son.
  • Michael Moreland as William O'Connor.
  • Robert Jack as Alan.
  • Owen Whitelaw as Fergus.
  • Paul Rattray as Steven.

Where can I watch My Son?

My Son is currently streaming on Prime Video through the Lionsgate+ subscription add-on. If you've not already purchased the add-on Lionsgate+ offers a seven day free trial to try out its offering which includes My Son.

Other projects you could watch in that seven day trial include the movies LaLa Land, the entire Twilight saga, and TV shows including Nashville and Mad Men.

That should keep you busy for a few days!