Otto Von Furth was a mine worker in East Berlin, Germany, where an unexpected cave-in trapped him and four fellow workers for 7 days. During that time, they were exposed to lethal levels of radiation which killed all of Von Furth's co-workers, leaving him as the sole survivor.
They had been mining highly radioactive radium and Von Furth nearly succumbed to its deadly rays. Miraculously, however, he survived. Once rescued, Von Furth was brought to a local hospital, but he was soon kidnapped by an ex-Nazi known as General Zahl.
In his own laboratory, Zahl used Von Furth's radioactive body for further experiments, subjecting him to chemical testing that resulted in a massive mutation. Von Furth's body changed into unstable protoplasm, and he was brought into the newly formed Brotherhood of Evil, where he took the name Plasmus.
He went on to battle the New Teen Titans with the Brotherhood of Evil and get his revenge on General Zahl when the Brotherhood caught up with him and Madame Rouge in Zandia.
Afterwards the rest of the Brotherhood of Evil reforms into Society of Sin. He is later recruited into Lex Luthor's Suicide Squad where he apparently dies fighting Imperiex.
Apparently alive again Plasmus came into conflict with the Teen Titans and became a member of the Secret Society of Super Villains, he was seen bombing Blüdhaven during the Infinite Crisis.
One Year Later
He again came into conflict with the Teen Titans, criticaly wounding Kid Devil though he is later defeated. He is next seen being exiled with many other villains during Salvation Run, In the final issue Lex Luthor uses him as a power source for a teleportion device and is seemingly killed when it self-destructs.
Along with Phobia and Warp he is sent as part of the Brotherhood to retrieve the Blue Beetle Scarab from El Paso, Texas.
Plasmus's touch causes a fiery death and causes living creatures to be reduced to burning protoplasm.
In the third season, subtitled Outsiders, Plasmus appears for a few episodes. Plasmus is the result of Markovian mad scientist experimentation on children. Plasmus has translucent skin, exposing his brain sitting inside his chest.
Plasmus appears in the Teen Titans animated series as a normal human being when he's asleep. When he's awake, however, he transforms into a simplistic mud-like monster.
Teen Titans Go!
Plasmus appears in an episode of Teen Titans Go!. He is shown on an alien planet, destroying a building with a giant sign that says "Do not punch". He later explodes, causing the planet to get destroyed.