In 1769, British Royal Navy officer John hears that his lover, an enslaved African woman,
has passed away and left a child named Dido behind.
John goes to the slums and rescues Dido, promising to give her the life she deserves as the daughter
of a captain.
Unfortunately, he can't take her with him on a ship, so John leaves her at the house
of his uncle William, the Lord Chief Justice, and his wife Lady Mansfield.
Both of them plus the spinster Lady Mary, the manager of the household and governess,
refuse to accept Dido under their care because of the color of her skin, but John reminds
them Dido is his blood and she should have the same rights.
Since they have no other choice, Dido is accepted in the household.
She feels awkward being there at first, especially when she notices that the paintings where
the old lords of the house have a black person with them, they are always on the back as
subordinates.
Dido also meets Elizabeth, another of William's nieces, who is living there because her widowed
father remarried to a woman that pressured him to disown the kid.
The girls quickly become friends and grow up together as sisters, Elizabeth never treats
Dido as anything but her equal even as they become ladies.
One day, Dido receives devastating news: John has died on duty and left her two thousand
pounds a year, making her an heiress.
In theory, this should make her a very good potential marriage candidate, but William
doubts anyone would want to sully their family name by marrying a black woman.
Sometime later, the Ashford family will be visiting them, yet Lady Mary forbids Dido
from having dinner with them; she's only allowed to join them after the meal.
Dido asks William how she can be too high in rank to dine with the servants yet too
low to dine with her own family, so William has to explain that dinner with guests is
a complicated, formal affair and her new money can't erase those formalities.
Elizabeth tries to defend Dido, trying to dine with her, but she isn't allowed to because
part of the point of this dinner will be trying to match Elizabeth with one of the Ashford
boys.
In the evening, Lady Ashford comes to dinner with her sons Oliver and James, and James
quickly takes interest in courting Elizabeth.
Meanwhile, Dido goes for a walk outside and is startled to see a man sneaking around.
It turns out to be John, the vicar's son, who only took a shortcut to bring a letter
for William.
After dinner, Dido gets to meet the Ashfords.
The mother immediately calls her a slur and James thinks Dido's repulsive, but Oliver
thinks she's intriguing like an exotic flower.
Oliver begins considering courting Dido, sending her smiles whenever he can, but James disapproves.
So does his mother, but she quickly changes her mind when she hears that Dido received
her father's fortune.
After Elizabeth is done entertaining everyone with a song, Oliver asks Dido to play as well.
This is new to her because she's never played for guests before, but she manages to impress
them all with her skill.
Sometime later, an artist is hired to make a portrait of Dido and Elizabeth together.
Dido gets upset because she thinks she'll be portrayed in the same way the other black
people appear in the house's paintings, so she rushes to complain to William, who is
in the middle of a meeting with John.
William tells her they'll discuss this later and asks her to take his books back to the
library; while she does so, she gets to hear what John and William are discussing.
It turns out John wants to be taken under William's pupillage to be a lawyer, and they're
discussing what law means to them.
John thinks the law should provide certainty to those that don't have it and brings up
the case of the Zong ship, which is under trial because they want the insurance company
to pay for their drowned slaves.
He also expresses his wish to one day make laws that can make the world a better place,
and when William points out he's just a country boy, John reminds him that William used to
lack money too and he only got to his position thanks through the favors from other lords.
Impressed by this answer, William asks Dido if he should take John as his pupil.
Dido refuses to answer, but that's enough for William to accept.
Afterward, John thanks Dido for her support since silence speaks louder than a thousand
words, and Dido takes the chance to ask about this Zong case.
John explains that the slaves were drowned by the crew themselves, but before he can
explain why, Dido is called to dinner.
It's then that John notices Dido isn't allowed to eat with the guests and is appalled, but
Dido just tells him this isn't the kind of matter a mere vicar's son should comment on.
Later in the evening, Dido looks at herself in the mirror and freaks out at the thought
of her own skin.
Days pass and John does well with his apprenticeship under William, but he also keeps bringing
up the Zong case because he doesn't think human lives should be discussed as "cargo".
He thinks William could use his power to speak against slavery, but William refuses to discuss
the subject further.
Dido is always very aware of John's presence in the house and tries to pretend it doesn't
make her feel things she shouldn't be feeling.
One afternoon, while Dido is sitting for the painting, John comes by to see her and she
gets the chance to ask more about the Zong case, because she's learned everyone in town
is talking about it but she's sheltered.
John explains the slaves were thrown into the water chained together as one, they also
were diseased, worth more as dead insured merchandise than alive as spoiled goods.
The insurance company is appealing because they're refusing to pay for murdered slaves.
When William learns that John has shared this information with Dido, even if it's public,
he gets furious and fires John, forbidding him from seeing Dido again.
After seeing John leave, Dido sneaks into William's office to look at the paperwork
regarding the Zong case and get a better understanding of the situation.
Her snooping is interrupted by Elizabeth, who asks her to come with her because their
aunt and uncle have big news for them.
In a few days, they'll be going to London, but only Elizabeth will be "coming out" to
society as a lady, not Dido.
Elizabeth needs to meet as many men as possible to choose a good match since she needs a husband
to provide for her, unlike Dido who has her inheritance.
Not believing what she's hearing, Elizabeth tries to defend Dido, but her uncle won't
listen.
William reminds them nobody will marry Dido so he offers her the keys to the estate, hoping
she'll become the keeper of the house to replace Lady Mary when the time comes.
He swears he loves and cherishes Dido, but she feels this is a punishment and refuses
to take the keys.
Afterward, Elizabeth hugs Dido, offering her sympathies and support.
When the four women go to London, Elizabeth comments she can see herself falling in love
with James, but Mary laughs at the idea of possibly marrying for love.
Worrying about her cousin, Dido reminds her that love may leave her poor or broken-hearted.
In return, Elizabeth calls Dido lucky for having her inheritance because she won't depend
on a man; sadly, most other women are nothing but a man's property.
In the house they're staying at there's a black maid, and Dido can't help feeling awkward
when she sees her, but the maid is understanding and even teaches Dido how to take care of
her Afro-textured hair.
In the afternoon, they visit the Ashfords and Elizabeth gets to spend time with James.
Oliver offers his company to Dido, too, ignoring James' protests, although James begins keeping
his racist comments to himself when he realizes Elizabeth won't take them well.
Elizabeth is a little worried that Dido is doing it on purpose to defy William, but actually,
Dido has a lovely time with Oliver, and when evening falls and the party starts, Oliver
expresses his wishes to court Dido properly, which Dido doesn't know how to take.
Later, Dido and Oliver bump into John, and having both men seeing each other makes things
too awkward so John decides to leave.
When the fireworks start, Oliver is distracted by them and Dido takes the chance to go after
John, who takes her into a dark spot to avoid being seen, although Elizabeth notices them
anyway.
Dido apologizes to Oliver for losing the apprenticeship since it's her fault, but Oliver's simply
glad to hear she's still trying to keep up with the news instead of going back to being
sheltered.
He and other law students are trying to fight for human rights and to appeal against insurance
companies accepting people as cargo, which would be the first step into slavery abolition.
Dido wants to keep discussing the subject, but soon the others will notice she's gone,
thus John sends her back after telling her which tavern he gets together at with the
other students if she ever wants to come by.
Meanwhile, Lady Ashford is trying to arrange the marriage of Elizabeth and James with Lady
Mansfield and Mary, but she calls it off when she hears Elizabeth doesn't have a single
penny.
Furious, now she wants Oliver to concentrate on courting Dido.
The next morning, Dido is extra aware of the black maid and asks William if she's a slave.
William assures her she isn't because she is free and gets paid a salary, so Dido counterattacks
by asking about the Zong case and calling it a "fraud".
Angry, William refuses to take a side on the case and Lady Mansfield cuts the conversation
short, calling it too vulgar for breakfast.
Later, William is approached by Oliver's father, who reminds him of his duty as a neutral judge
and wants to make sure William's love for Dido will get in the way of what he considers
the "right" choice on the trial.
The lord also takes the chance to discuss the matter of marriages, and later in the
afternoon, with William's blessing, Oliver shows up to ask Dido's hand.
She's quite shocked so she can't help hesitating at first, but soon she accepts.
Elizabeth is upset because no message came for her too and asks Dido what it feels like
to be engaged.
Dido answers it's perfect, but it's clear she doesn't mean it.
The next morning, Dido thanks William for his blessing.
Lady Mansfield wants to start looking for new candidates for Elizabeth, who wishes to
wait for James but is told to be realistic.
Dido notices Mary is reading a new pamphlet with news about the Zong case, so after breakfast,
she sneaks into William's office again to find some incriminating documents that prove
that when the Zong crew said killed the slaves because they were out of supplies to take
care of them, they were actually lying, because the ship passed by many ports without stopping
to restock.
The slaves' quarters were also overcrowded, which is what made them sick.
Dido steals these documents and, after the other ladies of the house are gone with Elizabeth
to find her a husband, Dido convinces the family driver to take her downtown.
Moments later, Dido finds John at the tavern and gives him the documents to help with the
cause.
Then, they go for a walk together while Dido keeps her hood up not to be recognized.
Dido takes the chance to confess she feels guilty because she knows she's lucky since
she's free both as a black person and as a woman, yet the pressure of getting married
feels like she's looking for a master.
John tries to compliment her, but Dido stops him by pointing out she's engaged to Oliver,
and when John asks if that's what she truly wants, Dido just makes excuses about doing
the necessary thing to keep the rank she deserves instead of being a spinster like Mary.
In John's eyes, she's reducing herself for the sake of rank and she deserves someone
that would marry her even if she were poor.
When Dido returns home and hears Elizabeth complain about how hard it is to find a husband
that is both suitable and wealthy, Dido wonders what happens if the man is suitable but you
don't feel like "yourself" with him.
However, Elizabeth is sure that she had love with James.
Some days later during another party, everyone keeps gossiping about Dido's engagement and
Elizabeth's desperation, although at least she gets an offer from another suitor.
When Dido gets a moment alone, James approaches her to insult her and touches her inappropriately,
claiming she'll ruin his family and that he has no use for Elizabeth.
Afterward, James goes back to his brother to express awful sentiments about the incoming
marriage.
Since then, Dido begins sneaking downtown any chance she has to see John, to both spend
time with him and keep on learning about the Zong case.
John confesses his aunt had tried to arrange a marriage for him too, but he turned it down.
The maid covers for Dido saying she's out with the other ladies, but one evening, William
sees her arriving alone and has a talk with the driver.
Later that day, Dido finds Elizabeth sad because she never heard from James again.
To cheer her up, Dido promises her to give her part of her inheritance for her dowry
so she can find a good husband, but when Elizabeth tries to use this to get James back, Dido
confesses what kind of awful man he is.
Thinking Dido is trying to hurt her on purpose, Elizabeth refuses to believe her, mentioning
James would never touch somebody beneath her and calling Dido illegitimate.
Dido responds by pointing out her father at least acknowledged her, unlike Elizabeth's,
and this causes Elizabeth to leave in tears.
At that moment, Dido sees arranged marriages for what they truly are and takes off her
engagement ring before sneaking out again.
Unfortunately, William sees her and goes with her downtown, getting her and John together
to give them a last warning.
John feels insulted for being told he would sully Dido's reputation and calls out William
for his swallow beliefs on human nature before confessing he loves Dido with all his heart.
Dido is touched, but she still sends him away because she thinks he doesn't deserve all
this.
Once he's gone, Dido points out her father would've never behaved like this.
When William returns home, he rants to his wife about Dido ruining her chances with a
perfect husband and John's naive activism.
However, Lady Mansfield shows her understanding of Dido because she had been lucky: when she
married William, he already loved her, but she can't imagine getting together with a
man she doesn't truly know.
She also calls out her husband, reminding him that once upon a time he also talked about
changing the world, yet he has done nothing since he became a judge.
Some days later, they learn about James getting engaged to another woman.
Elizabeth cries her hear out and Dido comforts her, so Elizabeth takes the chance to admit
she knew about Dido and John but didn't say anything because she wanted Dido to trust
her with that information.
Understanding, Dido admits she should've and is grateful to hear that Elizabeth thinks
she should choose the man she loves.
When Lady Ashford and Oliver come by, they're furious to hear Dido is calling off the engagement
and Lady Ashford uses less than favorable words to refer to her.
Dido stands up to herself and explains she refuses to marry into a family that would
feel ashamed of her the same way she's been taught to feel ashamed of her mother, these
words hit William hard as well.
When the painting is finally finished, Dido is shocked to discover she's been painted
as Elizabeth's equal, and William promises it'll be displayed in the house together with
all the others.
William can't feel noticing Dido's reading Thomas Day, who gave voice to people like
her mother, and he can't help wondering what else Dido wants because she never seems to
have enough.
As her uncle, he already defied lots of conventions to give her a good life, and Dido reminds
him that he hasn't defied the most important one.
The day of the trial, William arrives at court and overhears John speaking about the law's
responsibility to protect people from others but also from themselves.
Law mustn't only sanction, it must also prevent.
John sees William too and reminds him of his responsibility because Dido wasn't a slave
by mere luck and William's decision could mean living in a world where his beloved niece
could be classified as cargo.
William just answers that John shouldn't allow his emotions to guide his law studies.
When the time comes for William to give his verdict, he notices Dido has sneaked into
the courthouse and finally decides to do the right thing.
He presents all the evidence of the mistreatment of slaves and reminds everyone is not legal
nor right to kill for compensation, no matter if the life is human or animal.
William calls it a fraud and fails in favor of the insurance, establishing the first precedent
against slavery.
After the trial, William sees Dido and John together and blesses their marriage, but only
if John becomes a gentleman, meaning he shall become William's apprentice again so he can
become a lawyer.
Once William is out of sight, Dido tells John she loves him too and the two of them finally
kiss.
The real Dido and John got married and had two sons.
The real Elizabeth eventually married too and had three kids.
The Zong massacre became a seminal step towards the abolition of slavery.
The real painting of Dido and Elizabeth hung at the estate until 1922, and nowadays it
hangs at Scone Palace in Scotland, William's birth place.