Martin Watt had compiled a list of “bad guys” including addresses and car registration numbers of individuals linked to earlier disciplinary proceedings against him.
However, he told the High Court in Glasgow that the “template” was based on a film about mercenaries hired to kill.
Jurors heard that the the 62-year-old lost his job as an A&E consultant at Monklands Hospital in Airdrie, North Lanarkshire.
Police went on to find three Skorpion sub-machine guns, two Valtro pistols and bullets during a search of his home in Cumbernauld, North Lanarkshire, last May.
Watt yesterday insisted he had no intention to kill – and that he was “not a danger to the public”. But prosecutors said the police had “played a valuable service” by “capturing” Watt when they did.
Watt, who worked for the NHS for 32 years and was based at Monklands until 2012, denies a charge of possessing weapons with intent to endanger life.
Jurors were told he was dismissed after disciplinary proceedings.
Watt said the names on the list were involved in the “bullying, harassment and [his] eventual dismissal”.
His QC John Scott asked Watt: “What were your feelings towards these people?”
The ex-consultant said: “Monumental disappointment. I felt so cheated. They were trying to make it look like things I was not … being incompetent, racial abuse was also one. They were not allowing me to clear my name.”
Watt then told the court that he had “assessed how to assassinate” people on the list and “express my thoughts on paper”.
He said the plans were based on the plot of a film called Killer Elite, which Watt stated centred on violent mercenaries.
Mr Scott: “How to assassinate these people … that is quite a statement?”
The QC: “Any intention to carry out this plan?”
The former medic admitted he had firearms and bullets.
But he told the trial that he only used a Skorpion sub-machine gun for target practice at a forest area close to a motorway near his home.
The trial, before judge Lady Stacey, continues.