Sean Cassidy comes from an old Irish lineage that predates historical records.[11] A former Interpol agent,[12] and NYPD police officer,[13] Banshee, as he came to be known, possessed the mutant ability to generate "sonic screams", capable of harming human auditory systems and even breaking through inch-thick steel.[14] After the death of his wife, Maeve, Sean made some questionable decisions with his life, including getting involved with the villainous organization Factor Three. This path, however, led him to meet the famous super hero team called the X-Men, and, with their help, he returned to the right side of the law.[14][15][16] As an ally of the X-Men, Sean had countless adventures and eventually joined the team, when most of the original roster quit.[17] His life was apparently back on track as he fell in love with Dr. Moira MacTaggert,[18] found the daughter he never knew he had,[19] and became the teacher of the next generations of young mutants.[20] The supposed death of Moira would once again shake his world, leading him to resort to alcoholism as a coping mechanism.[21][22] Still, he would end up having a noble demise, giving his life as a last effort to save an airplane full of innocents (who unfortunately perished nonetheless).[1] Since then, three times has Sean been revived as consequence of evil plots,[2][4][6] and three times has he fought to make his return meaningful before being returned to the after-life (with various degrees of success).[2][5][7] Recently, he was resurrected by the Five and reunited with his daughter on Krakoa, this time finally restoring his joyful personality as well.[8]