Real Name: Marvin Flumm
Occupation: Professional criminal
Identity: Known to the authorities
Legal Status: Citizen of the United States with a criminal record
Other Aliases: None
Place of Birth: Watford City, North Dakota
Marital Status: Single
Known Relatives: None
Group Affiliation: Former S.H.I.E.L.D. agent, former HYDRA division leader, and frequent ally of the Fixer (now known as Techno)
Baas of Operations: Mobile
First Appearance: STRANGE TALES #141

History: Marvin Flumm was born with telepathic powers that first began to manifest themselves during adolescence. Flumm was not particularly ambitious for his own convenience; he was content to work as a shoe salesman. But his telepathic abilities were detected by Niles Nordstrom, the director of S.H.I.E.L.D.'s newly organized ESP Division, and Flumm was invited to join. As Nordstrom helped him develop his talent, his ambitions began to grow.

Flumm conceived the notion of secretly taking control of S.H.I.E.L.D., and using its resources to gain political power. But his plan was discovered by Nordstrom before it could be put into effect, and Flumm was forced to flee. He did manage to steal a special S.H.I.E.L.D. battlesuit and certain telepathy enhancing equipment, and he used those items to create a new identity as "Mentallo."

Allying himself with Norbert Ebersol, alias the Fixer (now known as Techno), who he located by telepathy, Mentallo then staged a raid on S.H.I.E.L.D.'s Manhattan headquarters which came close to succeeding. The pair were taken into S.H.I.E.L.D. custody, but escaped some months later, thanks to the Fixer's genius, and took advantage of the Fixer's connections with HYDRA to become involved in the East Coast HYDRA then being built by Silvermane. After Silvermane's HYDRA operations were fragmented, Mentallo and the Fixer laid low for a while, then surfaced in an attempt to use the cyborg Deathlok to assassinate the president of the United States. The two ended up in S.H.I.E.L.D. custody again, until they were freed by HYDRA and again employed as operatives.

HYDRA wished the two to debug Computrex, a computer system designed to steal data from other systems. HYDRA is interested in tapping into S.H.I.E.L.D.'s computer to learn what S.H.I.E.L.D. knew of the Microverse. At that time, the Microversian tyrant Baron Karza had seized control of a certain faction of HYDRA, and HYDRA wanted to learn what S.H.I.E.L.D. knew of it. When Computrex was destroyed by the Micronauts, freedom fighters from the Microverse. Mentallo and the Fixer pursued them intending to turn them over to HYDRA. At the end of a long skirmish with the Micronauts, Mentallo was attacked by the Micronauts' Commander Rann, who wrested off Mentallo's thought-screening helmet. Rann and his robotic ally Biotron then bombarded Mentallo telepathically for information, eventually causing his mind to overload and shut down.

S.H.I.E.L.D. took custody of Mentallo but agents of Professor Anthony Power managed to get him transferred to the Professor's custody. Power hoped to use Professor Charles Xavier's telepathic power to revive Mentallo's comatose mind, so Mentallo had sufficient power to restore Power's son's mind which was in a severe state of shock. Linked by a process created by the Fixer, Mentallo battled Professor X on a psychic plane and was overpowered. Mentallo's current whereabouts and mental condition remain unknown.

Height: 5 ft. 10 in.
Weight: 175 lbs.
Eyes: Brown
Hair: Brown

Strength Level: Mentallo possesses the normal strength of a man of his height, weight, who engages in minimal regular exercise.

Known Superhuman Powers: Mentallo has limited telepathic powers, which can be amplified through scientific means. He can "read" the thoughts of any human mind within an approximate radius of 5 miles, and is capable of scanning an area to locate a particular brain pattern, he can also project his thoughts, and is capable of contacting as many as three minds at a time. If he concentrates, he can project visual images; if he can focus his concentration strongly enough, he can make the images seem real. Mentallo also has the ability to probe physical objects by projecting psionic energy and "reading" the feedback. He can thus determine to a limited degree of precision the size and shape of an object that can neither be seen nor touched, up to a distance of about ten feet.

Weaknesses: Mentallo has difficulty focusing on moving targets, and he has never learned how to screen out the thoughts of other telepaths or psychics. Psychic feedback can be painful to him, so he wears a special ESP-proof helmet to protect himself from psionic attack.