What an extraordinary performance from newcomer Vicky Knight, who has to carry an entire film on her shoulders. Her task is doubly astounding considering that her character, Jade, is severely damaged—both inside and out—and bringing her to life requires a vulnerability that would likely frighten even the most seasoned actors.

In the new film “Dirty God,” Jade’s name alone provides insight into her soul. We see in the opening that Jade bears horrible scars, and director Sacha Polak (who co-wrote the film with Susanne Farrell) lingers somehow lovingly on what we guess are skin burns about her face, shoulders and torso. Jade even wears a plastic mask over part of her visage. But this is no trick of makeup; I learned that Knight in real life was trapped inside a house set alight by an arsonist when she was eight, and though she was fortunate to escape alive, relatives of hers perished. It’s difficult to even imagine the actress’s pain, but the physical scars she brings to Jade are her own. However, Jade’s underlying psychological burns are far more damaging, as we will discover.

Polak’s choice to show Knight’s skin in extreme close up at the start was a brave, but wise, choice. There is no getting around that her hero appears this way, and thus her choice of shots allows us to then forget Knight’s physicality in favor of her extraordinary performance.

After the harrowing opening, we follow Jade to a clinic, where doctors inform her there is little else they can do to fix her scarring. Yes, Jade would like to look normal again, not just out of vanity but because her new face frightens her daughter Rae. Jade lives at home with her mother Lisa (Katherine Kelly) on the outskirts of London. Severely upset that the toddler is now scared of her, Jade increasingly leaves Rae in Lisa’s care. Thus her nights are left free to go clubbing with her best mate Shami (Rebecca Stone) and Shami’s beau Naz (Bluey Robinson). In the dark of the clubs, Jade can be observed but not fully seen by drunken suitors. This activity she complements with meeting random men online for masturbatory sessions, typically without revealing her face.

We learn the horrid reason for her disfigurement: An on-and-off boyfriend, who is also Rae’s father, splashed acid in her face. This is treated matter-of-factly in an early courtroom hearing; a lesser film would have lingered over the court proceedings, but “Dirty God” is smarter and wisely gets back to plumbing the depths of Jade’s rage.

Since the NHS (the U.K.’s version of our own Health and Human Services) will not pay for more surgery, Jade believes she has found the solution in a shady online ad for a reconstructive surgery operation in Morocco. It would set her back nearly 4,000 pounds that she does not have, so Jade reluctantly takes a job at a call center, where she befriends Flavia (Dana Marineci), also a single mother.

This job is key to unlocking Jade’s true damage. Working in a call center requires patience, which Jade has in short supply, and often dealing with people at their worst. Jade frequently tells off callers, and any decent supervisor would have sent her packing (particularly after a fight breaks out in the office when Jade is humiliated by something she would much rather not go public). She isn’t made for this job—or, likely, any. Jade is a screamer and swears liberally even at those who try to make her Rae’s life easier. But as Lisa informs Jade at one of the film’s most searing moments, Jade is incapable of seeing to anyone’s needs but her own, including for her own daughter.

Thus the genius of “Dirty God” is to present us with a protagonist whose inner ugliness is now matched due to her ex-boyfriend’s assault. It is almost as if the scarring gives Jade the permission she has always sought to act in an anti-social fashion. What is truly amazing about Knight’s performance is that she nonetheless makes us empathetic to Jade. Yes, it is horrible that she was so disfigured, but Knight’s bravura performance and Polak’s assured direction remind us that this doesn’t give her specific license to ignore her child or to otherwise purposely hurt those around her.

“Dirty God” requires Knight to be exposed psychologically and physically, for scenes of both medical and erotic nature. She has more than one nude scene, including a rather intense sex scene with a person whose desire for her has not been lessened by her disfigurement. There is no hiding the scarring that covers parts of her breasts, but Knight is unconcerned with modesty. The film reminds us that sexuality is not solely the provenance and the privileged, or of the perfect and the unblemished.

The crux of the second half revolves around Jade’s trip to Morocco for what she hopes will be a life-altering plastic surgery. She is joined on the journey from England by Shami and Naz, and the trio’s dynamic, already complicated by past events, will reach its nadir, especially on the day of Jade’s surgery.

As in life, there are no easy answers for Jade, as much as she hopes otherwise. It’s a hard lesson, and one she will no doubt have to impart to Rae as the toddler grows up. Lisa, Jade’s mother, already knows the nature of the world and has made her peace with it. If only Jade can learn to do the same. Thus, there are no “happy” endings in “Dirty God,” only a hope that the hero will make better decisions going forward.

Vicky Knight is a revelation as a first-time professional actress, and what she brings to Jade is remarkable in its nuance and depth. It is just that an actress with her physical marks was selected rather than applying makeup to a better-known performer. Actors are too often lauded as “brave” for looking less than perfect on screen, but though they could be made to look the part of Jade with makeup, only someone with Knight’s experience could bring her so fully to life.

I hope Knight continues to act and that, as with the deaf actress Marlee Matlin, whose roles rise far above being hearing-impaired, future roles will call on her to give life to characters who just happen to be scarred, rather than that be their defining characteristic. If “Dirty God” is any indication, Knight has a brilliant acting future ahead of her.

“Dirty God” is now available on demand and in select theaters.