Da Wikipedia:
The comic features two spies, Black and White, who are constantly warring against each other. The typical plot is always the same: one spy is planning a scheme to kill the other spy; then the other either turns the plan against him or comes up with a brilliant counterplan of his own.
The title panel of the comic almost always features a one-panel gag presenting one spy besting the other; the main comic then uses the rest of the panels to tell a different short story with the other spy winning.