One of the Shadow King's minions deepens the link between him and April in an attempt to permanently take their shared heart away from her, which backfires and creates an even stronger link between them. April finds her personality being partially overcome by the Shadow King's and develops the ability to create shadow-swords, which is worsened when her father is released from jail and starts harassing her and her mother, awakening her long-boiling rage at him. But the connection turns out to work the other way when April seeks comfort by sleeping with Ram, causing the King himself to be overcome with desire for a minion...
At the climax of the episode, Ram and April's mother manage to persuade her not to kill her father, but she channels the King's power to do something unclear to her mother. Meanwhile, a further attempt to deepen the connection gives the King the exact location of Earth, and he declares an all-out attack on the planet. April is aware of this through their link, and pre-emptively uses her shadow powers to create a portal to the King's world and jump through it, intending to challenge him. Ram jumps through the portal after her.
Meanwhile Charlie disturbs Matteusz when he behaves increasingly arrogantly towards Miss Quill, and when he confesses that the Cabinet contains billions of Rhodian souls who could potentially destroy another species in a suicide attack... and that there is also a legend that the power of a true hero could enable them to permanently take over the bodies of, rather than destroy, other beings.
In a further subplot, the Coal Hill area is being gradually over-run by bloodthirsty carnivorous alien tree blossoms. The new headteacher, Dorothea Ames, who is somehow fully informed about Charlie's and Miss Quill's true natures and past, offers Miss Quill the chance to have her parasite removed if she helps destroy them.
Tropes that appear in the episode:
- Absurd Cutting Power: April is able to create a rift to the Shadow Kins' world using her swords.
- Absurdly Sharp Blade: April's swords, or scimitars, can even create an entrance to the Shadow Kins' world.
- An Offer You Can't Refuse:Dorothea Ames: How would you like to get that little creature out of your head once and for all? How would you like your own free will back to do whatever you please?
- Blue-and-Orange Morality: Defied, Charlie claims that his situation with Miss Quill is fair according to the morality of his planet. Tanya doesn't buy it and claims that the situation is slavery and wrong anywhere in the universe.
- Cliffhanger: April creates a portal to confront Corakinus on his home ground, and Ram jumps in after her before it collapses.
- Continuity Nod: Mrs. Ames refers to Charlie's assumed surname of "Smith", and alludes to the Doctor's common pseudonym of "John Smith".
- Did You Just Have Sex?: After Ram calls to inform the rest of the group that the Shadow King Corakinus is possessing April, Tanya correctly guesses that they (meaning Ram and April) had sex. Charlie misinterprets the pronouns, and asks if Ram and Corakinus had had sex.
- Explosive Breeder: The carnivorous blossoms split into three or four when they feed.
- Fate Worse than Death: Due to her link with Corakinus, April considers soldiers who ran away to suffer this, claiming "Who'd want to live as a coward?"
- Fertile Blood: Just a drop of blood can make the petals multiply at an exponential rate.
- Fire and Brimstone Hell: The Shadow Kins' world looks exactly like this.
- Glowing Eyes: April when she connects to the Shadow King.
- Hydra Problem: The petals, which duplicate when they feed on blood.
- Interrupted Intimacy: His connection to April prompts the Shadow King to have sex with Kharrus when April starts having sex with Ram. However, because April finishes way ahead of him, Corakinus suffers some "performance issues" before completing his own mating.
- Last Stand: Invoked. April, while connected to Corakinus, says the soldiers at Dunkirk should have fought and died.
- Man-Eating Plant: The petals, which reproduce using blood.
- Mook Promotion: Corakinus tells Kharrus there is room on the throne by his side if she succeeds in keeping the heart in his body.
- Not Himself: April starts talking about how soldiers and how cowards should be weeded out of the army in a class due to her link with Corakinus.
- Out-of-Character Alert: April talking about how soldiers sign up to die in class, due to her mental connection with Corakinus.
- Parents Walk In at the Worst Time: April's mother finds her and Ram naked together in bed, having obviously just had sex.
- Psychic Link: As a result of the attempt to anchor the heart in Corakinus, one is formed between April and Corakinus, where they can hear each other's thoughts.
- Red Eyes, Take Warning: April's eyes turn red due to her link with Corakinus.
- Rejected Apology: April's father, Huw, claims that he just wants forgiveness from her and her mother. However, what he did to them in the past is so horrible that they aren't willing to talk to him, let alone forgive him, and suspect him of being insincere and just wanting to force his way into their lives again.
- Relationship Upgrade: April and Ram have sex for the first time, becoming an official couple.
- Rhetorical Question Blunder: April, while connected to Corakinus, asks who would want to live as a coward, to which another student replies "Most people?"
- Self-Duplication: The petals, which keep duplicating.
- The Swarm: The Petals.
- Throwing Off the Disability: April heals her mother's spine using her Shadow Kin powers.
- Titled After the Song: The title refers to the song "Owner of a Lonely Heart" by Yes.
- War Is Hell: April's link to Corakinus causes her to deliver a talk about war and how people always die.
- You Have Failed Me: The King kills two successive minions for failing in attempts to unshare his heart.
- You're Not My Father: "You are not my father anymore! You are not a part of this family!"
