Sandra first appeared in 1999, 15 years prior to the main events of the film, when Joseph was on the phone in his office, with their son Ford waiting outside with a "Happy Birthday" banner, intending to surprise his father. Before heading to work at the nuclear power plant in Janjira, Sandra and Joe took Ford to school, where she wished Joe a happy birthday before sharing a tender moment.
Under Joe's supervision, Sandra assembled a small team to perform a damage check at the power plant's core, after the plant starts to experience seismic activity. During the breach, she attempted to evacuate her team to safety, at Joe's insistence. Unable to make it out in time before Joe was forced to shut the door, she became a casualty of the nuclear accident, along with her entire team.
Joe sees his wife for the final time behind the glass window separating him from her before the bulkhead shuts her away and the power plant collapses. Both her son and husband were left distraught by her death.