Edward is much older than his comrades. In fact, he was around when the Bombs dropped in 2077, having been established as one of Vault 44’s robotic doctors, due in part of being programed with extensive medical skills and ethics. He would be responsible for maintaining the health and well-being of the Vault’s citizens, in cooperation with Vault-Tec staff. However, upon analyzing some new medication that Vault-Tec was pushing upon the citizen early on, he found that the chemicals in this medication would greatly diminish the denizen’s free will and would allow for brainwashing. Edward addressed this issue to his superiors but they told him his prime directive is to “Serve Vault-Tec” and he should not impede in this program. However, Edward would find himself at a paradox, which resulted in an unexpected effect: he would reject his prime directive of “Serve Vault-Tec” and instead follow the Hippocratic Oath. He then sought to dismantle Vault Tec’s plot and would apply this “glitch” to the operating systems of the other Mister Handy units (including Mister Gusty units) to help put the people before the company. This action, however, lead to the Mister Gutsy units putting matters in their own hands and wipe out the Vault-Tec staff behind the scheme.
This resulted in Vault-Tec’s experiment being revealed and upended and the denizens free from their influence, but Edward couldn’t stand the fact he caused numerous deaths, even if he saved the freedom of countless more. Out of penance, Edward chose to exile himself from the Vault and into the Wasteland. He’d travel for some time, but as it was only a few years after the bombs dropped, there wasn’t anyone around. What people he’d find, he’d perform medical aid to them but was otherwise alone. Eventually, he’d power himself down, as he expected he’d never see another living soul for some time. It would be nearly 200 years later when he’d be discovered; a ghoulish con-man named Eddy and his idiot super mutant companion Ed somehow reactivated Edward’s systems. While the two wanted to have Edward be their “robot butler” (despite him being a Doctor Handy model), he would only accept to be their robot companion if they can help him return to Vault 44 and see of its state. He would be brought to Quad City and discover that Vault 44 had not only survived but has thrived and helped bring civilization back to the Midwest (though a tad limited by the Enclave’s, Supremacy’s and Reaver Movement’s attacks). Satisfied to see his Vault alive, free and happy, he concludes to uphold his end of the deal and become Eddy’s and Ed’s companion, and with it, become a Vault Cracker.