Niall Rafferty (real name Matthew McQueen) played by Barry Sloane made his first appearance on the 3 December 2007 and his final appearance less than a year later on the 27 November 2008 where his character was killed off. He was central to a storyline involving the already-established and it was revealed Niall was the illegitimate son of Myra McQueen (Nicole Barber-Lane). The storyline featured Niall seek revenge on the McQueen's, which concluded in highly advertised episodes featuring Niall kidnapping his siblings and causing the death of sister Tina Reilly.
Niall arrives as a new hairdresser at beauty salon, Evissa. He helps Evissa owner Louise Summers (Roxanne McKee) and attacks her fiancé Warren Fox (Jamie Lomas), who assumes Niall is mugging her. Niall befriends co-worker Carmel McQueen (Gemma Merna) and her family. Jacqui McQueen (Claire Cooper) is suspicious of Niall, who claims to have two sisters. Niall soon becomes friends with Myra, who is unaware of his identity, and is invited for Christmas. Overwhelmed, Niall steals a picture from the McQueen's and burns it. Niall attempts to become closer to his mother and begins encouraging her to be stricter with Michaela McQueen (Hollie-Jay Bowes). Niall gets Michaela drunk at a party and injects her with heroin, which causes her to overdose and makes the McQueen's believe she is addicted. Niall continues his revenge on the McQueen's by ruining their lives in small ways; reporting Myra for benefit fraud, pushing Carmel and boyfriend Calvin Valentine (Ricky Whittle) apart and attacking his grandmother, Nana McQueen (Diane Langton).
Niall grows closer to Steph Dean (Carley Stenson) following her split with boyfriend Max Cunningham (Matt Littler). Niall falls in love with Steph, and is devastated when she and Max get back together and agree to marry. On their wedding day, Niall speeds off in his car, angered that Steph married Max. Unknown to Niall, his car is in the path of Tom Cunningham (Ellis Hollins). Realising Tom is about to be hit, Max pushes him out the way of the car, but is run over and killed himself. Niall feels guilty for causing Max's death and is pushed away by Steph. Niall reveals an affair between John Paul McQueen (James Sutton) and Kieron Hobbs (Jake Hendriks). Niall overhears Tina Reilly (Leah Hackett) telling Jacqui over the phone she wants to give her unborn child up for adoption. Out of anger, Niall pushes Tina down a flight of stairs, which causes her to have to undergo an emergency hysterectomy and give birth to her son Max McQueen premature. Jamie 'Fletch' Fletcher (Sam Darbyshire) witnesses Niall's assault, but due to his drug addiction, Niall convinces everyone that Fletch pushed Tina.
Niall convinces Kieron to leave John Paul and the village, to get him out of the way. Niall bonds with John Paul in Kieron's absence, but is annoyed when he returns. Kieron tracks down Myra's long-lost son and discovers Niall's secret. After confronting him, Niall admits the truth, but drugs Kieron's beer. Kieron is killed and Niall uses his phone to text John Paul to make him think Kieron committed suicide. Niall later tries to drug John Paul in the same way, but discovers John Paul switched their drinks. John Paul eventually leaves Hollyoaks with ex-boyfriend Craig Dean (Guy Burnet). Niall's life begins to go wrong after Steph tells him she cannot love him. Niall decides to begin his plot of revenge. He kidnaps each of the McQueen children, leaving notes for Myra, who becomes suspicious after discovering baby Max with a note which mirrors the one she left with a new born Niall. Niall then confronts Jack Osborne (Jimmy McKenna) after learning he was the police officer who arrested Niall's biological father, who died in prison. Niall tells Jack the truth and attacks him. Myra tracks her children down to the same church she left Niall in, and is shocked when Niall reveals the truth. Niall tells her she has to answer six questions, and for each she gets wrong, one of her children will be killed. Myra gets two questions correct and is forced to choose between her children. Tina and Michaela are allowed to live. However, Jack, Darren Osborne (Ashley Taylor Dawson), Tony Hutchinson (Nick Pickard) and Dom Reilly (John Pickard) arrive to save the McQueen's. Realising his plan may be stopped, Niall detonates explosives and the church blows up. In the wreckage, the floor collapses and Niall finds Myra caught under rubble and attempts to free her with help from John Paul. She explains if Niall had told the truth, she would have accepted him. Feeling guilty, Niall pushes Myra out the way as more rubble falls. As the McQueen's escape the church, Tina dies from her injuries. As an ambulance drives away, Niall's reflection appears in the window, revealing him to have survived. The McQueen's believe Niall is dead. However, the police tell them that Niall's body was never recovered and that he is still alive.
Niall arrives back in Hollyoaks, with the McQueen's no longer his target. He follows Steph and Tom to Scotland, where Craig takes them for a break. In the hills, Niall spies on Steph and after a day of waiting, kidnaps Tom. Niall reveals himself and tells Steph he wants to talk. Niall traps Steph on a cliff edge and fights with Craig, who he attempts to kill. However, Craig makes Niall look at a scared Steph. Realising everything he has done, Niall says goodbye to Steph and falls backwards over the cliff. Several days later, the McQueen's are told of Niall's death, but agree not to mourn him.
In December 2012, a new born baby boy was abandoned on the McQueen's doorstep on Christmas Day. After learning that the baby belongs to John-Paul, he names his son in honour of Niall, but by his real name, Matthew.
- Kieron Hobbs-Niall Poisoned Kierons drink killing him.
- Max Cunningham-Niall Was Drunk And He Drove His Car And Struck Max Killing Him.
- Tina Reilly-Dies In The Explosion That Niall Caused By Detinating The Bomb.
- Total: 3 (2 Straight up Murders, 1 Manslaughter)
"WOAH!" (First line, in response to Louise Summers as she trips over and he rushes to help)
"Bye Steph." (Final line)