Whistleblower, the BBC’s flagship undercover series, is back, this time investigating the health and safety of the food in some of Britain’s supermarkets.

Following tip-offs from whistleblowers the team went into action, sending undercover reporters into selected UK supermarkets. The findings, which might make some viewers think twice about certain trusted brands, will be shown in tonight’s programme

Previous Whistleblowers have exposed bank fraud and malpractice in a High Street bank; sharp practices by estate agents; the criminal world of bailiffs; corruption amongst car-parking attendants; serious security lapses at UK airports; danger on Britain’s railways; and looked into the sales practices of a major finance company.