Real Name

Len Brown

First Appearance

T.H.U.N.D.E.R. Agents #1 (1965)

Original Publisher


Created by

Len Brown and Wally Wood


Formerly a corporal in the U.S. Army, Leonard "Len" Brown was an employee of T.H.U.N.D.E.R. who was stuck in a desk job and not happy about it. But T.H.U.N.D.E.R.'s inner council called upon him to wield an invention of the late Professor Jennings, an “electron molecular intensifier belt” or “Thunderbelt” (as he called it). Len Brown became the T.H.U.N.D.E.R. Agent Dynamo.

Dynamo is a tough, stoic, basically decent, somewhat beleaguered super-everyman who can be a little bit overwhelmed by the weird circumstances he finds himself in as well as the pressures of his job, but always manages to carry on no matter what. His bosses are always riding hard on him for not taking proper care of the belt, and eventually they altered the belt so that it would automatically turn off after thirty minutes.

He is also somewhat nervous around women in spite of his remarkable ability to attract them. Fellow T.H.U.N.D.E.R. employee April Robbins and T.H.U.N.D.E.R. Squad member "Kitten" Kane (before she fell in love with Lightning) both fell for his charm. He and April casually dated, although he often flirted with other women. But perhaps his greatest romance was with one of T.H.U.N.D.E.R.'s foes, the ruthless Iron Maiden. She captured Dynamo for the Warlord and tried to force him to reveal the secret of the Thunderbelt. When he refused and proved able to resist her truth serum she became impressed with his strength and power and fell in love with him. Dynamo had very definite sexual tension with her and mourned her when he thought she'd died after the battle with Dr. Death. Iron Maiden clashed with Dynamo several times afterwards and once framed him as a traitor to force him to join her, but she also came to his aid against other villains a number of times.

Besides Iron Maiden, other foes of Dynamo include Red Star, Doctor Sparta and a mysterious race of alien invaders.

Powers and Abilities

Dynamo uses an “electron molecular intensifier belt” (Thunderbelt) which increases the mass of its wearer and makes him superhumanly strong. But the mass increase creates an enormous strain on the user and even someone with great stamina, like Brown, can only use it for thirty minutes at a time. It was attuned to Brown's metabolism so that only he could use it. He also wore a metallic costume that would protect him when he couldn't use the belt


Dynamo makes short work of some tanks. From T.H.U.N.D.E.R. Agents

Public Domain Appearances

  • T.H.U.N.D.E.R. Agents #1-20
  • Dynamo #1-4
  • NoMan #2


  • "Len Brown" was also the name of the writer who co-created Dynamo. However, unlike many self-insert characters, Dynamo showed a certain amount of vulnerability and had concrete limitations to his powers.
  • Dynamo was originally meant to be called Captain Thunderbolt and his design was loosely based on that of Captain Marvel.

See Also

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