A quarter of Scots believe MI5 spies are "working with the UK government to try and stop Scottish Independence", according to research carried out for BuzzFeed News by polling firm YouGov.
The poll found 26% of Scots think it is "probably true" that the security services are trying to stop the country voting for independence on 18 September. The finding illustrates the incredibly low level of trust in UK institutions among some parts of the Scottish public.
A further 20% of Scots said they "don't know" whether MI5 is actively working to keep Scotland part of the UK, while 55% said they thought the suggestion is "probably false".
The poll of 1,084 Scottish individuals was carried out over three days from 3 September by YouGov. The company questioned the same individuals on their voting intention in a poll for this week's Sunday Times that showed the pro-independence campaign has moved into the lead for the first time, with just over a week to go until the vote.
Senior Scottish nationalists have previously suggested British spies could be engaging in a dirty tricks campaign to stop Scotland breaking away from the rest of the UK, although there is little evidence to either support or disprove this suggestion. The government does not comment on MI5's activities.
The now-deceased Margo MacDonald MSP wrote to the chiefs of Britain's security services in 2013, urging them not to let their spies interfere in the independence debate. In addition, former SNP deputy leader Jim Sillars told The Independent he believes British secret agents are active in Glasgow and suggested it is "naive" to imagine MI5 is not taking a role in the independence campaign.
The poll also found that almost half of Scots believe the Westminster government is hiding new oil reserves found in the North Sea during the referendum campaign.
North Sea oil underpins the economic case for Scottish independence and the dispute over the value and quantity of the remaining reserves has been constant throughout the referendum debate. The pro-independence Yes Scotland campaign promotes suggestions that new technology could release an extra £600 billion worth of oil, while Better Together says such claims are wildly optimistic.
When it comes to how much oil there is in the North Sea, perceptions are just as important as reality. One Downing Street source told BuzzFeed News that a particular theory involving David Cameron hiding the existence of a secret oilfield is "bollocks", but with 42% of Scots believing the Westminster government is hiding the truth about oil reserves, such denials are clearly not having the desired effect.
And finally, the poll found that 19% of Scots believe the referendum will probably be rigged.
Which will give the vote organisers cause for concern.
The polling was undertaken using YouGov's online panel, which offers rewards to individuals who share their opinions.
This article originally said that Margo MacDonald, who died in April, was an SNP politician. Although originally a member of the SNP, she left the party in 2003 and sat as an independent politician until her death.