Jake Wolfe is an agent with the CIA.
Was an agent, a bit of time before we first meet in. Will be an agent again as time passes and his unique and impressive skillset is called for.
When we meet him, he is living in the San Francisco Bay area working as a photojournalist for a local paper and living with, or more accurately planning of ending his living with, a woman named Gwen who comes across as a nutcase but may prove to be even worse. He is also getting over the loss some time previous of his war dog. He is close friends with a SFPD police lieutenant named Terrell and may put emphasis on his picture taking to crime scenes.
We discover that he and Terrell have been best friends since they served together in the Marine Corps over in the Middle East years before. After their tours ended, Terrell return to SF and joined the police. Wolfe got invited to go work for the CIA which he did for several years.
The connection with the Agency ended when his handler decided for whatever reason to leave Wolfe up to his neck in trouble in the desert, certain that there was no hope of getting Wolfe out alive. Wolfe chose to not be so obliging as to die on cue and now his attitude towards the CIA is not so favorable and towards that handles is bordering on homicide.
We learn a lot about Wolfe's former career from a Secret Service agent named Greene who was reviewing Wolfe's file. "The file also revealed he'd been trained by the CIA to kill a person with a fist, a ballpoint pen, a belt, a credit card, a toothbrush, an electrical cord, a chair leg, a car key, a beer bottle, and all kinds of other items. She knew that not long ago Jake had been one of the top animals in the jungle food chain. He had killed the killers and terrorized the terrorists, and he'd saved a lot of innocent lives by doing it. He'd also been promised by the government that his dangerous work was all supposed to be behind him now. Yet here he was today. So much for promises from bureaucrats."
Wolfe will, in the course of that first recorded adventure, take great pity on another Marine war-dog named Cody whose master was a good friend of Wolfe who had succumbed to drugs. At the funeral for his friend, Wolfe decided for the sake of the dog who was suffering from PTSD that he would adopt him and for the remainder of the adventures the two will remain extremely close and make up one impressive team.