From the outside, Miguel and Sofia seem to have everything sorted. They live in a beautiful London home, have two children and successful careers, but it does not take long for Bunker to show that things are not quite as perfect as they look. A dispute over a hole in the garden wall starts things off, but before long, paranoia, resentment and some different ideas about money, security and what actually matters begin putting real pressure on their marriage.

Javier Bardem plays Miguel, an award-winning Spanish architect living in London with his wife Sofia, played by Penélope Cruz. Their very polished life is disturbed when their neighbour Toby, played by Stephen Graham, knocks through the wall between their properties to install a window in his converted garage. Miguel is furious about the loss of privacy, which, to be fair, is understandable, but the argument comes at the same time as another offer that starts pulling him in a different direction.

Miguel is approached by an extremely wealthy tech billionaire who wants him to design a huge underground bunker on a private island, somewhere his family can survive if society collapses. The money would change Miguel and Sofia’s lives, but Sofia is horrified by the idea of helping someone that rich shut himself away from everyone else when the world goes wrong. From there, the bunker becomes more than the obvious underground structure. The film starts looking at the walls people build around their homes, their relationships and themselves, and how protection can quite easily turn into isolation.

Penélope Cruz and Javier Bardem Are Brilliant Together

The biggest reason Bunker works is Penélope Cruz and Javier Bardem. Knowing they are married in real life adds something to watching them play a couple who have spent years together but are slowly moving further apart, and there is a real familiarity between them that the film never has to force.

Cruz is fantastic as Sofia. A lot of her frustration is there before she even says anything, whether it is a look across the room, the way she reacts to one of Miguel’s comments or the feeling that she has heard the same story from him one too many times. She has left a career and life in Madrid behind, is unhappy with where she has ended up professionally in London, and you can see that resentment building without the film needing to spell out every part of it.

Bardem is just as good. Miguel is not some awful husband who suddenly turns into a villain, which makes the relationship a lot more believable. He loves his family and thinks he is protecting them, but the more uneasy he becomes, the more obsessed he gets with controlling what is happening around him. Watching him slowly disappear into that fear is one of the film’s strongest parts.

Stephen Graham is also great as Toby, the neighbour responsible for the whole garden-wall argument. His scenes with Bardem have a bit of dark humour to them because, technically, Miguel has a point, but Toby has absolutely no intention of making things easy for him. Paul Dano also pops up as the billionaire behind the bunker proposal and makes a strong impression despite only appearing briefly, bringing just the right amount of smugness to the role.

The House Becomes Part of the Problem

The Moreno family home is almost a character in itself. It is gorgeous and modern, all glass and clean lines, but the longer we spend inside it, the more claustrophobic it becomes. Miguel grows more fixated on privacy and security, eventually installing an elaborate system to keep people out. The house ends up feeding the same fear and isolation that is already starting to take over his life.

That idea runs through the film quite clearly. Miguel wants privacy from Toby, the billionaire wants protection from everyone else, and Sofia feels more and more trapped inside a life that probably looks enviable to anyone standing outside it. None of this is especially subtle, but the performances stop it from feeling completely heavy-handed for most of the film.

Visually, Bunker looks gorgeous too. The house gives Zeller plenty to play with, from its huge windows and open spaces to the way Miguel and Sofia are framed further and further apart as things get worse between them. For a film about people shutting themselves off, there is something quite clever about setting so much of it inside a home built almost entirely around openness and glass.

Sometimes Bunker Explains a Little Too Much

Where Bunker loses us slightly is when it starts explaining ideas that are already clear. Florian Zeller comes from theatre, and you can feel that in some of the longer conversations between the characters. Plenty of those scenes work because Cruz and Bardem are so good together, but there are also moments where the dialogue starts telling us something the film has already shown perfectly well.

The symbolism around walls, windows, bunkers and people trapping themselves inside their own lives is strong enough on its own. There are points where the film underlines it once too often, as though it is worried we might not have noticed what it is doing. We noticed, Florian. You can trust us.

The final section also pushes much harder into thriller territory, and that is probably the part that worked least for us. Things become much more dramatic very quickly, and after spending so long watching the tension build through Miguel and Sofia’s marriage, the shift feels a bit much. It does not undo everything that came before, but the film is stronger when it keeps the focus on the relationship and lets the unease build naturally.

For CultureCues, we really liked Bunker. Penélope Cruz and Javier Bardem are brilliant together and completely carry the film, with Stephen Graham also doing exactly what Stephen Graham does and making every scene he is in better. The house, the paranoia and the slow breakdown of Miguel and Sofia’s relationship all work really well, even if the film occasionally explains itself a little more than it needs to. The final act goes bigger than we would have liked, but there is still a lot here to enjoy. It is tense, beautifully made and worth watching for Cruz and Bardem alone.

CultureCues Rating: ★★★★☆ (4/5)

Bunker is screening as part of the BFI London Film Festival 2026.

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