Brian Braddock pursued post-graduate studies in Physics at Thames University, while Betsy worked as a charter pilot. Soon after Brian became the hero Captain Britain, Betsy alerted him that their brother Jamie had been injured, while testing his racing car in the grounds of Braddock Manor, apparently an attack rather than an accident. Betsy flew Brian back to the Manor, but their plane was downed as they neared the crash by the psychic powers of Dr. Synne; luckily both inside survived the crash. Dr. Synne subsequently mind controlled Betsy into seeing her brothers as hideous monsters, causing her to attack them, but they managed to overpower her.
Betsy was taken to the nearby Morder Research Center for treatment, unwittingly delivering her into the hands of one of Synne's agents, Dr. Ramsey. When Brian managed to defeat Synne, things only worsened. Freed of Synne's mind control, Ramsey reverted to his true allegiances as an agent of the Nazi,Red Skull, taking both Betsy and Jamie as hostages. Both were subsequently freed by Captain Britain and his new ally, Captain America. It was after this that Betsy experienced her first reported psychic incident (there may have been earlier, unreported ones, but Synne's mind control appears to have unlocked her psychic potential, allowing it to start to grow). Betsy had a precognitive dream warning her of Brian's peril fighting the mad Lord Hawk.
Betsy quit the charter business and took up modeling. Some time later, with her psychic powers growing and after Brian had departed overseas to continue his studies, Betsy made mental contact with aS.T.R.I.K.E. Psi agent (S.T.R.I.K.E. being Special Tactical Response for International Key Emergencies, the U.K.'s equivalent of the U.N.'sS.H.I.E.L.D.agency), and was soon recruited by Agent Matthew (later renamed Gabriel), with whom she pursued a brief romance. Betsy subsequently became the lover of fellow psi, Tom Lennox. Maintaining her modeling career as a cover, at one point, Betsy attempted to infiltrate the Hellfire Club, where her father had been a member of the London Branch's Inner Circle, holding the position of Black Bishop, for S.T.R.I.K.E., but was warned off by Tessa. Betsy had lost track of her brother for many years while he was adventuring in America and other dimensions, but he returned in time to save her life when she and her fellow S.T.R.I.K.E. Psi's were targeted for assassination by Slaymaster, who had been hired by the crimelord, Vixen, to cover her takeover of the agency. Betsy, Tom, and the sole other survivor of the Psi Division, Alison Double, sought refuge with Brian in Braddock Manor, but had to flee there after a battle between Brian, his allies (the Special Executive), and the hero killing, extra-dimensional, cybiote theFury.
With the insane mutant reality-warper, Mad Jim Jaspers, taking over the country, the group sought to hide out in London. While in London battling Crimson Dynamo, Betsy shared a intimate night with Hercules. Later, Tom was killed and Betsy and Alison captured by government forces. The two women ended up in a concentration camp until Jaspers' reign was brought to an end, partially through the efforts of her brother. Betsy, who had been in mental contact with Tom when he died, met and convalesced under the care of Victoria Bentley, an old friend of Dr. Strange and the Black Knight, at the camp and Victoria not only helped her heal, but taught her to harness the trauma she had felt, using it to develop and strengthen her psi powers.
The purpose of her bionic eyes was revealed shortly after when Mojo, using Psylocke's eyes as a camera, transformed the X-Men into the X-Babies to film their adventures. The New Mutants battled the de-aged X-Men until they were broken of their brainwashing and defeated the spineless one, Mojo. The massacre of the Morlocksoccurred shortly thereafter and Betsy was charged with helping the wounded and staying in telepathic contact with the members that were in combat with the Marauders. After the initial conflict, Betsy fought the savage Sabretoothin a brawl throughout the mansion. Impressed by Besty's courage, the battle-ravaged X-Men offered her a position on the team and Betsy accepted and adopted the codename Psylocke. Next, Betsy battled Malice with the X-Men.