In Tate Taylor’s adaptation of the bestselling novel The Girl on the Train, Emily Blunt plays Rachel, a woman whose obsession with a picture-perfect couple leads to her involvement in a missing-person case. We meet Rachel through her own internal narration, but it quickly becomes apparent that what we see in Rachel is different from what she sees in herself. Rachel is an alcoholic, and her dependence on drinking has become debilitating ... and potentially murderous. The Girl on the Train might not be a cinematic achievement to last a lifetime, but if you can manage to ignore the distraction of the beige murder plot that makes up most of the film’s runtime, the movie is an opportunity to witness Emily Blunt serving up the unhinged glory of that rarest and most precious of all movie archetypes: the sloppily riveting Lady Drunk.

Though recent looks at alcoholism on film like Smashed and Krisha play addiction straight, portraying the fall of the alcoholic into dysfunction, the Lady Drunk genre stands apart from realism. The Lady Drunk is an icon, not a portrait. If the alcoholism film makes a story out of the life of the alcoholic, the Lady Drunk enters a story that might have existed soberly without her ... and inevitably wreaks havoc on the lives of the unenlightened. Amy Schumer didn’t come out of nowhere with her ode to hot messes in Trainwreck — the Lady Drunk is a time-honored tradition in movies, a figure responsible for some of the best performances and films in the canon of American cinema, encompassing Bette Davis in All About Eve, Elizabeth Taylor in Who’s Afraid of Virginia Woolf?, and Gena Rowlands in just about everything. These are larger-than-life portraits — impressions of women unbound — but despite the spectacular heights the Lady Drunk has traditionally offered, the character has struggled to find her way to the big screen as women’s films increasingly take a backseat in studio filmmaking. As in many women’s genres, it’s television that has kept the tradition alive, with heroes like Lucille Bluth, Alicia Florrick, and Olivia Pope functioning as modern versions of the messy queens of yore.

Compared to the boardroom power moves that have come to accompany many of the best Lady Drunks on television, Rachel’s life in The Girl on the Train lacks the glamour of TV’s best winos. She’s lonely, she wrestles with guilt, her self-esteem is at rock bottom, her memory dips in and out with her drinking. Yet as portrayed by Blunt, she retains an element of magnificence that is lacking from the lives of the stylishly sober women she envies throughout the movie. They have their self-control, their husbands, their fancy houses, but only Rachel functions as a larger-than-life image.

In life, the dissolution of the self that alcoholism facilitates is a terrifying threat to the relationships and well-being of the addict, but in this regard, it is crucial to acknowledge the difference between watching a performance and watching a real person. Narratives are not life. Watching The Girl on the Train, we know Emily Blunt is performing Rachel’s slurs, we know her real-life marriage hasn’t fallen apart, we know she’s not embarrassing herself, we know what we’re watching fundamentally has no consequence in the realm of reality — and so Rachel’s disorientation is a matter of guiltlessly hypothetical voyeurism. Removed from the lasting pain of alcoholism as a disease, drunks at the movies function as a glimpse of the individual unbound from self-control. Because the movie drunk is only superficially destructive, it’s possible to look past the equally superficial wreckage to experience the thrill of transgression and last-ditch creativity that accompanies the wreck.

The Lady Drunk is an icon of failure, but perversely, it’s exactly those failures that fuel her power as an image. Where it remains rare to see a fictional female character let loose from responsibility in either public or private, the first and most important feature of any Lady Drunk is always her failure to be a lady, in the socialized sense of the word. Whether or not the character in question has lost her ability to control her drinking or never desired that control in the first place, the Lady Drunk is a vacation from social responsibility — she exists in a plane of uncontrollable excess. She not only flagrantly fails to reenact the familiar codes of femininity that govern the public sphere — the small talk, the manicured appearances, the tactful discretions — but she is also incapable of fully perceiving her own inability to perform. As motor functions are obliterated by the interference of alcohol in the mind, the storytelling conventions that demand normative womanhood are obliterated too.

At the movies, alcoholism acts as the great narrative leveler, the supreme solution to the problem of gender. In cinematic alcoholism, we watch a woman who is unable to comport herself as a woman. Within the realm of feminine archetypes, we enter a realm of gender ambivalence, as if in a fable where all the action begins with a shot of magic elixir.