Get Smart, on NBC (s1-4) / CBS (s5)
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Maxwell Smart, aka Agent 86 (played by Don Adams) was a secret agent who worked for CONTROL, along with his partner, Agent 99. Max was not too bright, kind of bumbling, not very professional, joked a lot (though sometimes it was less than 100% clear whether he was joking or just clueless). But he was still a pretty good agent, somehow. Max, by the way, was much more often called by his real name than his code number, though I don't think we ever heard 99's real name. Um, and their boss was called "Chief." And their major enemy was an organization called KAOS, whose top agent was named Siegfried, though their missions pitted them against plenty of enemies besides KAOS. Anyway, um... it was a really funny show which you should definitely try to check out. Not sure what else to say, but hopefully I'll get a chance to watch more of the series someday (at which point maybe I'll expand on this review, and quite possibly give it a higher rating).
Oh, and Don Adams later provided the voice of the title character in the 1980s animated series Inspector Gadget. And in 2008, there was a Get Smart movie, starring Steve Carell as Max Smart.