They wouldn't let him quit.

Icarus

Trained KGB assassin, Edward Genn (code name ICARUS), worked years ago as a sleeper agent in America. But when the Soviet Union collapsed, he quickly found himself in a foreign country with no one to trust. Determined to escape his muddled existence, Edward tries to start over. He assumes a new identity, starts a family and tries to start his own legitimate business that could potentially pull him out of his world of being a hitman.