Like all Time Lords, Spandrell was taken from his family at the age of eight for the selection process in the Drylands. Staring into the Untempered Schism as part of a Time Lord initiation rite, Spandrell was inspired by what he saw in the Schism. (PROSE: A Brief History of Time Lords)
Spandrell was Castellan during the President's assassination and led the subsequent investigation into the attack. He was very sceptical of the Fourth Doctor at first but ended up becoming his ally in the unmasking of Chancellor Goth as the President's murderer. While Spandrell was Castellan, it was rare for the office-holder to deal with criminal offences committed by Time Lords; according to Engin, his duties more often brought him into contact with "more plebeian classes". (TV: The Deadly Assassin)
Spandrell was persuaded to come out of retirement to serve under Lord President Flavia. (PROSE: Blood Harvest, Happy Endings, The Eight Doctors) By the time of Romana's presidency, Andred was castellan. (AUDIO: Lies)
Spandrell was tough and sardonic, with his long years working in Security making him a cynical individual. His career ensured that he had no illusions about the underside of Gallifreyan life and gave him a blunt and no-nonsense manner. His survival was thanks to his integrity and efficiency. (PROSE: Doctor Who and the Deadly Assassin)
Spandrell was of average height and was, for a Time Lord, unusually broad and muscular. He had an impassive and heavy face that disguised his vast intelligence. (PROSE: Doctor Who and the Deadly Assassin)
Behind the scenes
According to NOTVALID: Dalek: Spoof Scenes, in a version of events where the Last Great Time War was fought against the Drashigs rather than the Daleks, the Ninth Doctor cited Spandrell as one of the people who'd perished in the War, alongside Damon, Drax and the Meddling Monk.