Thomas is a Freelance Photographer down on his luck. He has been evicted from his apartment, dumped by his girlfriend, and now forced to live on the hard streets of New York City. To make things worse he just discovered that the pain he's been feeling in his lower abdomen is from Testicular Cancer. With only the support of his one true friend, his dog Vader, Thomas agrees to a free experimental treatment. The details of the treatment are shady at best. But now in the later stages of cancer, broke and desperate, Thomas is willing to take the risk.
Miraculously, Thomas is completely cured but there has been an unexpected side effect. The testicle removed from Thomas has now taken on a life of his own and calls himself Lefty. Lefty has grown to the size of a large beach ball and becomes super intelligent. He decides that he and Thomas will become superheroes. With resources provided by the same mysterious doctor who performed the surgery, Thomas becomes Mr. Ballsy and Lefty becomes ... well he's still Lefty. Together they set out to detect cancer cells in people who are not yet aware of their condition.
Life for Thomas has done a complete 180. He now has a new found mission in life, a beautiful wife, a newborn son and a new friend Lefty. But Lefty was not the only side effect of the doctor's experimental treatments. A cancerous creature has been hidden in the dark corners of the facility. There it has been multiplying and growing. The creatures are discovered but not completely defeated. Some of the creatures escape and spread throughout the world.
Now Mr Ballsy and Lefty have a second mission. They have to detect these cancerous creatures wherever they are as soon as possible before they grow too strong to destroy. This will be no easy task because the creatures adapt and evolve.
This is where the adventures of Mr Ballsy begin!