Captivity
Captivity is a recurring motif in the novel for key plot highlights. At the beginning of the novel, a man is kidnapped by a supernatural man who can fly. Kaz kidnaps Van Eck's wife in exchange for the kidnapping of Inej. Initially, Van Eck is held as a hostage by the Dregs until he proves his worth to the crew. Matthias was incarcerated at Hellgate where he was held captive for a while. Nina was held captive by Fjerdan where she meets Matthias.
Ship
The novel is set during the period of sea travel and ships are a crucial part of this story throughout. It symbolizes endings as well as new beginnings, depending on the characters in question. After an attack on the Grisha's in the city, the remaining population is smuggled out on a ship symbolizing a way out of chaos and a fresh start in a new land. Matthias and Nina met after their ship was destroyed and ended up helping one another. The destruction of the ship brought them together which blossomed into an ill-fated love and trust.
Sabotage
On occasion, situations go haywire and characters have to improvise to save themselves or their interests. Jesper's meeting with his father is sabotaged when they are just about to meet. During the exchange of hostages between Kaz and Van Eck, an attack by supernaturals takes place which forces them to split up. Kaz intends to sabotage silos belonging to Van Eck with a chemical agent that will surely disrupt the sugar market in the city. Before they can compromise the silos, they are surprisingly attacked by Pekka who has allied himself with Van Eck.
Disguise
Nina and Jesper preoccupy Van Eck's attorney away from his office, disguising their true intention; Kaz was sneaking into his office in search of legal documents belonging to Van Eck. During the auction, Kaz disguises the Grisha's to sneak them away from the embassy.
Crows
The crow is by far the dominant motif in the novel. The Dregs' gang symbol is the crow and the members wear it as a banner. As the leader of the Dregs, Kaz walks with a cane engraved with a crow's head. The gang headquarters is covered in crow banners and the place itself is called Crow Club. The gang resembles the bird itself in their traits; they are wild, unpredictable, and smart.
No mourners, no funerals
The Dregs' gang is the fiercest in the city, and they all live by a code which they must carry to their death. Since almost all members of Dregs are people without families or loved ones, they often utter the phrase "no mourners, no funerals" to signify that in the event they don't make it back alive, no loved one will lay them to rest or mourn them. They are trained to accept death at any moment and not cower in the face of it.
