From Wikipedia, the free encyclopedia

250px X FACT COV005 400 Siryn
Art by Ryan Sook.
Publication information
Publisher Marvel Comics
First appearance Spider-Woman #37 (April 1981)
Created by Chris Claremont
Steve Leialoha
In story information
Alter ego Theresa Rourke Cassidy
Species Human Mutant
Team affiliations X-Factor Investigations
Fallen Angels
Muir Island X-Men
Notable aliases Tracy Cassidy
Abilities Sonic scream, flight, Power of suggestion by voice modulation, enhanced hearing, sound containment.

Siryn (Theresa Rourke Cassidy) is a Marvel Comics superheroine, associated with the X-Men. Created by writer Chris Claremont and artist Steve Leialoha, she first appeared in Spider-Woman #37 (April 1981).

Like her father, the X-Men’s Banshee, Siryn is an Irish mutant, who possesses a “sonic scream” capable of incapacitating and injuring an opponent’s hearing and sending powerful vibrations through the air. She can use these vibrations to fly. Her name refers to the Sirens of Greek mythology.

Siryn was raised by Banshee’s cousin and arch-nemesis Black Tom Cassidy without Banshee’s knowledge. By her late teens, she has left Black Tom and joined the X-Men offshoots X-Force and X-Factor.


  • 1 Fictional character biography
    • 1.1 Early life
    • 1.2 Muir Island
    • 1.3 X-Force
    • 1.4 X-Corporation
    • 1.5 X-Factor Investigations
    • 1.6 World War Hulk
    • 1.7 Messiah Complex
    • 1.8 Divided We Stand
  • 2 Powers and abilities
  • 3 Other versions
    • 3.1 Age of Apocalypse
  • 4 Marvel Age
  • 5 In other media
    • 5.1 Films
  • 6 References
  • 7 External links

Fictional character biography

Early life

While Sean Cassidy was working on a deep undercover mission for Interpol, his wife Maeve gave birth to their daughter, Theresa. Not much later, Maeve died in an IRA bombing. With no means to contact Sean, his cousin Tom took care of Theresa. When Sean returned to learn of his wife’s death, he was devastated. Before Tom could even tell him of the existence of his daughter, Sean lashed out at Tom with his sonic scream for not having taken better care of Maeve. While Sean flew away in anger, Tom fell into a chasm, breaking his leg as a result of the attack, which left him with a limp. Angrily, Tom swore to make Sean pay and vowed to never tell him about his daughter, raising her himself instead.

Tom (now known as Black Tom) would raise Theresa as his apprentice in his criminal activities. Eventually, Theresa accompanied Black Tom and his then-partner, the Juggernaut, to San Francisco to assist him in his crimes. Here, employing the name Siryn, she battled the original Spider-Woman and several of the X-Men. This conflict ended in Black Tom’s temporary capture. While in custody, Black Tom exonerated Theresa of responsibility for her crimes and wrote a letter to Sean explaining who she was. The X-Men brought Theresa back to their headquarters, where she was joyfully reunited with her father.

150px Xforce90 Siryn

magnify clip Siryn

X-Force #90 where Feral injures Siryn

Muir Island

Theresa moved to Muir Island, home of the research laboratories of Dr. Moira MacTaggert, a longtime ally of Professor Xavier. While living on the island, Siryn started a romantic relationship with the mutant known as Multiple Man. This version of Multiple Man turned out to be one of his many duplicates and not the original Multiple Man, leading to the end of the relationship. During this time Siryn and Multiple Man traveled to New York City to help the New Mutants find two of their members, Sunspot and Warlock, who had run away from the school. In the course of this adventure, Siryn and Multiple Man met the association of street-level mutants known as the Fallen Angels.



magnify clip Siryn

Deadpool and Siryn, by Karl Kerschl

Siryn becomes a core member of X-Force, a paramilitary superhero team and for a time was its field leader. As a member of X-Force, her teammate Warpath develops a romantic interest in her while Siryn begins an on-going flirtation with the mercenary Deadpool. Deadpool and Siryn initially became involved when the two met while fighting Black Tom Cassidy and the Juggernaut. Though Banshee warns Siryn that Deadpool was a madman and a murderer, she found herself quite taken with him, even looking past his horrific appearance. Due to this kindness, Deadpool becomes infatuated with Siryn and often sat outside her window as she slept in the X-Mansion. At first Siryn is unaware of this, but she is comforted in knowing that he is watching over her. Over time, Siryn became the voice of reason and sanity in Deadpool’s ear, attempting to sway him to the side of good. She assists him in some of his missions, such as when Deadpool felt he needed some blood from the Hulk in order to cure problems with his own healing powers. In the end, however, Siryn becomes overwhelmed with balancing her duties with X-Force and the demands of Deadpool’s somewhat faulty sanity. She promises him that she would consider progressing their relationship if he continues on the path of good, and once she has her X-Force responsibilities secured. Warpath continues to seek Siryn’s affections, and makes his dislike for Deadpool clear during a visit to the baseball diamond used in the movie, Field of Dreams.

Siryn confronts varied adversaries during her time in X-Force. She helps put down a coup in the other dimensional realm of Asgard. She confronts the forces of Onslaught and the interdimensional media mogul known as Mojo. She even battles S.H.I.E.L.D. forces on more than one occasion. She also confronts more down to earth problems, particularly alcoholism. Warpath helps her to cope with her drinking problems, and as of recent issues of X-Factor she is leading a sober lifestyle.

She becomes a vital part of the team, as said so by an aspect of Charles Xavier[1], which saves the entire team from a near-death experience.

She leaves when Feral, a former teammate turned villain, slashes her throat, destroying her vocal cords and rendering her temporarily mute and powerless.


Thanks to the aid of Deadpool, Siryn has since fully healed from her vocal cord injuries. Deadpool tracked down Wolverine and stole a sample of his blood to heal her.

Siryn joins the Paris branch of the international mutant task force X-Corporation, where she reunites with old friends such as Multiple Man, Rictor and Cannonball, and works for the first time with M. Their first mission does not go well and Siryn has to deal with the loss of another friend, Darkstar.

X-Factor Investigations

Siryn leaves X-Corp to become a member of X-Factor Investigations. Siryn, as part of her initial duties for X-Factor Investigations, investigates the murder of a woman who died in a movie star’s penthouse, on behalf of the victim’s sister. A rival firm, Singularity Investigations, represented the actor with Damian Tryp, Jr. as the defense counsel and to prove the star innocent. When Siryn and X-Factor Investigations manages to incriminate the star, and to thwart SI’s assassination attempt on Rictor[2], Tryp Junior is so infuriated that he ambushes Siryn and beats her, leaving her to die in an alley. She was later rescued by Rictor.

Siryn is in a state of denial regarding her father’s death, holding to the fact that many X-Men have been believed dead only to later return alive.

Due to a love triangle with fellow teammates Multiple Man and Monet St. Croix, Siryn’s relationships with the X-Factor members are strained. During a night of drinking on Jamie Madrox’s part, Siryn ends up sleeping with Madrox, and St. Croix with his dupe. Both women are unaware that this had occurred, and are both hopeful of continuing a romantic relationship with him. Upon reabsorbing his dupe, Madrox is reluctant to tell the ladies, fearing for his life. Siryn resolves her differences with both Madrox and St. Croix, and the two women develop a budding friendship and partnership on later missions.

Theresa and Monet are sent to retrieve two famous child singers (who specialize in mutant hate songs) from their parents, thanks to a court order from their grandparents. The two end up being ambushed, knocked out, and kidnapped by the children’s mutant bodyguards, Solo and Clay. They awake imprisoned, (Theresa is tied up with her mouth covered by duct tape to prevent her from using her powers), but they both escape and return the children to their grandparents. It is revealed that the entire mission was a ruse by the mutant Josef Huber to lure the women away from their X-Factor teammates. Both Monet and Siryn’s mental-based powers negatively effect Huber’s mind-control abilities.

World War Hulk

Siryn answers the Stepford Cuckoos’ call for help when the Hulk assaults the X-Mansion in World War Hulk.

Messiah Complex

Theresa assists Rictor’s infiltration of the Purifiers, and accompanies M and Strong Guy, along with the rest of the X-Men, to rescue the mutant baby and X-Force. She later receives a call from the mutant Peepers, who is being pursued by Predator X, but Theresa arrives too late to help him and finds what is left of his corpse. Siryn prays at the comatose Jamie’s bedside when he awakes, and takes part in the X-Men’s assault on the Marauders’ base with Monet and Guido, taking on Exodus in the battle.

Divided We Stand

Siryn reveals that she is pregnant with Jamie’s child, and after talking with Monet she reveals she intends on keeping it. She has not yet told Jamie but when she tries, he mistakenly believes that she wants to quit X-Factor. Monet later realizes she still loves Jamie. Theresa then tries to tell Jamie again but Arcade makes his presence known in Mutant Town so X-Factor split up to deal with him and help the residents.

In X-Factor #32, Jamie sees a vision of Layla Miller who reveals to him that Siryn is pregnant with his son; Jamie apparently guessed this all along, as Layla is a representation of his subconscious. He later suggests to Terry that they name the child Nathan, revealing to her that he both knows about and accepts the child. The status of Terri and Jamie’s relationship is so far unrevealed, as Terri has stated she is in love with Jamie (though not to him) and Jamie originally intended to pursue romantics with her, before and after the drunken-duplicate-love triangle incident.

Powers and abilities

Siryn possesses sonic powers similar to those of her father, Banshee, although she is able to use her powers in ways that Banshee apparently cannot. Like her father, she can emit high-decibel “sonic screams”. She can also vary the pitch to deflect projectiles, and she even used it to deflect lasers once[issue # needed]. She possesses an enhanced sense of hearing and can use her voice for echolocation. While screaming, Siryn is able to fly. Siryn has especially potent sonic attacks. She can shatter objects; project concussive blasts of sonic force; or cause immediate pain, nausea/vomiting, and unconsciousness. She has shown a degree of immunity to what would be harmful and painful sounds to normal humans or mutants without sonic-based powers.[3]

She is vulnerable to losing the ability to use her power effectively by overstraining and overusing her sonic screams or injury to her throat and vocal chords.[4]

Unlike her father though, Siryn is able to influence and control other human beings with her sonics, as well as cause them to enter a hypnotic state[5]. Siryn can also cause the intended person to fall in love with her without regard to gender or sexual orientation and carry out her wishes and commands, like mythical Sirens.[6] Siryn deploys this ability on Spider-Man, leading him to divulge the truth about the Decimation of the mutants.[7]

In addition, she can also prevent others from hearing external sounds by a certain vocal pitch so that she can secretly deliver messages to them[8].

Other versions

Age of Apocalypse

Theresa first appears as a human in the X-Man arc of the AOA crossover. She alerts Nate Grey to an incoming attack by calling out to him, in doing so, activating her latent mutant abilities. She then accompanies him and his crew for the rest of the arc, culminating in X-Man being shunted into the 616 reality. In the AOA reality, Theresa did not go by the Siryn codename, instead going by Sonique.

Marvel Age

Recent solicitations from Marvel have confirmed that an adolescent Siryn will make her debut in “Wolverine: First Class” #6 from the company’s family friendly Marvel Age alternate universe imprint. [9] The issue will center around Theresa attending a sleepover thrown by Kitty Pryde, and preview art shows that she will have the blonde hair sported by the character in her earlier appearances.

In other media


  • In the film X2: X-Men United, Siryn was played by Shauna Kain in a small cameo role. During William Stryker’s attack on the mansion, her scream alerts the rest of the school that they are under attack. She was knocked out, but was rescued by Colossus. Her name (along with her father’s) also appears on a list of names Mystique scrolls through on Stryker’s computer while looking for Magneto’s file. In the novelization for the film (written by Chris Claremont), Siryn and a young Jamie Madrox are involved in a budding teen romance.
  • Kain reprised the role in X-Men: The Last Stand.


  1. ^ X-Force #68
  2. ^ X-Factor vol. 3 #3-4
  3. ^ X-Factor vol. 3 #30
  4. ^ X-Force vol. 1 #90
  5. ^ X-Factor vol. 3 #1
  6. ^ X-Factor vol. 3 #1
  7. ^ X-Factor vol. 3 #8
  8. ^ Cable & Deadpool #17
  9. ^

Attached Images:
Terms of Service | Privacy Policy | Report DMCA Violation