Code Name: Sergeant Klein
Original Name: David Holden
Status: Mysteron Agent
Partner: None. Does hire personal assistants from time to time.
Sex: Male
DOB: 08/05/2043
POB: Liverpool, England
Eyes: Blue
Hair: Dark Brown

Personal History: Information on Klein's background before Mysteronisation is limited. He was, however, described by many as reasonably intelligent, and had a friendly attitude to many. During his life, he was said to be skilled with computers and was often involved in the production of many computer-related items. Despite all of this however, Klein was also said to be dishonest at times, as well as being quite an independent person who prefers to keep some things to himself. Often seen wearing a green jacket, which sported Army Sergeant symbols, the origin of the name he uses, ‘Sergeant Klein’ is unknown. His death was caused when he attempted to try and stop two drunken men on Runcorn Bridge. Unfortunately, the two men, who were on the run from the Police, managed to throw Klein over the edge of the bridge and into the deep waters of the River Mersey, from which his body never emerged or was discovered from.

Since Klein's death, incidents have occurred that prove that he is now under the control of the Mysterons. Police continued their search for the two men who killed Klein, but soon discovered their bodies, partially buried under gravel, both with their throats slit in a horizontal line from below the left ear to below the right ear. Spectrum now believes that this murder method is Klein's ‘signature’ to show that he has murdered the victim. Sightings matching Klein's description have also been an extra supply of evidence. Rumours believe he is being used by the Mysterons for extreme undercover operations, due to how independent he is. He often uses false names to hide his identity.

Now a ruthless individual, Klein now has an attitude of pure hatred towards the people of Earth and mankind itself. An act he often performs is to bribe or threaten a person into assisting him if he feels it is necessary. However, recent incidents show that Klein almost always leaves no human alive who can give any leads towards his objectives. Klein himself usually carries out the deaths of all humans he feels may give his objectives away. In almost all circumstances, many people that work with him, or meet him, do not live to tell the tale.