Alex Deuyour – A 17-year-old wizard and the group's brains who is part of a prophecy along with Harry where the two of them will defeat Voldemort.
Harry Potter – Alex's second cousin and godbrother who is part of a prophecy to defeat Voldemort.
Ron Weasley – Alex's second cousin and godbrother who is loyal to Alex and Harry.
Hermione Granger – Alex and Harry's Muggle-born best friend who is the other brains of the group.
Kate Nguyen – Alex's ex-girlfriend and best friend who is a half-blood Gryffindor.
Matt Crocitto – Alex's best friend and a half-blood Gryffindor.
Sirius Black – Alex's maternal uncle and godfather and Harry's godfather and honorary uncle, who constantly checks on Alex and Harry by sending a Patronus and later by going to Grimmauld Place and later Shell Cottage.
Albus Dumbledore – The Headmaster of Hogwarts who was killed at the end of the previous school year.
Severus Snape – Alex's godfather and honorary uncle, who Alex trusts even after he witnessed him kill Dumbledore, and a Death Eater who becomes Headmaster of Hogwarts after Voldemort infiltrates and takes over the Ministry.
Remus Lupin – Alex's godfather and honorary uncle and a member of the Order of the Phoenix.
Alastor "Mad-Eye" Moody – A grizzled ex-Auror and member of the Order of the Phoenix who is paranoid.
Dudley Dursley – Harry's first cousin, who makes up with Harry.
Vernon and Petunia Dursley – Harry's maternal aunt and uncle and Dudley's Muggle-hating parents.
Molly Weasley – Ron's loving (but strict) mother.
Arthur Weasley – Ron's Muggle-obsessed father and an employee at the Ministry of Magic.
Fred and George Weasley – Ron's older brothers and twin pranksters who own a joke shop and host a radio podcast which rants against Voldemort and his supporters and make humor of him, as well provide news and announce deaths and disappearances.
Bill Weasley – The eldest of Ron's brothers and a member of the Order of the Phoenix who is a Curse-Breaker at Gringotts.
Fleur Delacour – Bill's fiancée and the former Beauxbatons Champion for the Triwizard Tournament during Alex and Harry's fourth year.
Charlie Weasley – Ron's older brother and a member of the Order, who tends to dragons in Romania and recruits members of the Order there.
Ginny Weasley – Harry's ex-girlfriend who attends Hogwarts and rebels against Snape and the Death Eater- controlled Hogwarts.
Nymphadora Tonks – An Auror and member of the Order of the Phoenix, who is pregnant and Remus' wife.
Ted Tonks – Tonks' father and a Muggle-born who is targeted by Voldemort because of his blood status.
Andromeda Tonks – Tonks' mother and a disowned member of the Black family.
Rufus Scrimgeour – The Minister of Magic, who is killed by Voldemort while protecting Harry.
Dean Thomas – A Gryffindor who is unable to prove his blood status and is on the run.
Griphook – A former goblin who worked at Gringotts.
Muriel – Ron's great-aunt who knows all the rumors about Dumbledore's past.
Elphias Doge – Dumbledore's oldest friend and a member of the Order of the Phoenix.
Rita Skeeter – A journalist who makes false accusations and ruins peoples' lives.
Bathilda Bagshot – The author of A History of Magic, who lives in Godric's Hollow and knew the Dumbledore and Potter families.
Garrick Ollivander – A wandmaker, who Voldemort kidnaps and tortures.
Gregorovitch – Ollivander's retired rival wandmaker, who previously owned the Elder Wand.
Gellert Grindelwald – Dumbledore's former lover and a dark wizard who is imprisoned at Nurmengard.
Kendra and Percival Dumbledore – Dumbledore's deceased parents who are painted in a bad light by Rita.
Phineas Nigellus Black – Sirius' great-grandfather.
Regulus Black – Sirius' younger brother who was killed by Voldemort.
Kreacher – Sirius' house-elf who respects him and the group after telling them the truth about Regulus.
Dobby – A house-elf who is loyal to Alex and Harry.
Luna Lovegood – An odd and eccentric Ravenclaw and the group's close friend.
Xenophilius Lovegood – Luna's father, who shares her odd and eccentric tendencies.
Lord Voldemort – Alex and Harry's archnemesis whose Horcruxes the group is destroying.
Bellatrix Lestrange – Voldemort's insanely devoted follower and Alex and Sirius' cousin.
Lucius Malfoy – One of Voldemort's Death Eaters who has fallen out of favor after failing to give Voldemort the prophecy.