In December 1976, Psylocke was introduced as a support character for her twin brother Captain Britain's title. Elizabth 'Betsy' Braddock was a Charter Pilot and Supermodel. She was quickly shown to have mutant telepathic powers and after various adventures including dying her hair purple, becoming a spy, briefly becoming Captain Britain and being blinded, Betsy was kidnapped by Mojo who gave her bionic eyes, brainwashed her and named her Psylocke. After being saved by the New Mutants, Betsy started to live with at the mansion and became a fully fledged member of the X-Men after proving her worth against Sabretooth.
Psylocke would serve the X-Men through the Mutant Massacre and the Fall of the Mutants until having to fake death and start a new life in Australia with her fellow X-Men. Psylocke briefly took reigns of the team only to have to send the reaming members through the Siege Perilous, a magical portal which renders the users amnesiac, in order to save all their lives from the Reavers. However, once rendered memory-less, Betsy was taken by Matsuo Tsurayaba, The Mandarin and the Hand and was her mind was put in the body of a japanese assassin known as Kwannon, creating the Psylocke we know today.
After a series of confusing months regarding who the real Psylocke was, Betsy regained her memories and personality. Although forever trapped in the ninja's body, Betsy finally realised her dream of being the warrior she always wanted to be. After years of loyal service with the X-Men, several power changes, a brief stint with death and time with the reality hopping Exiles, Betsy found her place with the X-Men again, re-joining them in San Fransisco and Utopia whilst become a member of Wolverine's covert kill squad X-Force and siding with Cyclops after the Schism.
Happy 35th Birthday everyone's favourite British, purple haired, telepathic, telekinetic, ninja, assassin, mutant, X-Man. You're one of a kind babe, here's to the next 35 years!