Cyberattacks are on the rise. Marks & Spencer, Co-op and Harrods have all been targeted. Public bodies, hospitals and schools have also come under attack from hackers who take over computer systems and demand a ransom to unlock them. Many victims simply pay up. With payouts in the millions, the hackers are getting away with huge sums. Panorama has been given exclusive access to the spies on the front line in the battle against the cybercriminals. Reporter Richard Bilton investigates the online crimewave and meets the secret agents trying to stop the hackers.