Without her, "Tabloid" would be a mediocre documentary, likely to end up on some specialty channel on TV. (The film is also flawed technique-wise, using fadeouts to a distracting degree.) But the film would be of similar quality if it featured only her. So Morris supplies outside opinion such as reporters from two tabloids who covered her story, an "accomplice" in her scheme, and an ex-Mormon missionary. This mix paints as full a picture of the situation as possible.
Renowned for being (apparently) extremely smart and beautiful, McKinney went to Utah when what seemed like a matchmaking opportunity opened up. She fell in love with Kirk, who she didn't know was Mormon. After hitting it off really fast and getting engaged, Kirk apparently left without any notice and sent Joyce on a wild goose chase to find him, resulting in her "rescuing" him from the Mormon religion and trying to trigger his supposed love of her via some unconventional techniques.
"Tabloid" goes on to cover how what happened was snapped up by the news and how McKinney was forced into stranger and stranger situations as a result. Since it goes full-bore into the story (as is per usual for Morris), those who are alienated by the idea should stay away. For those drawn in, though, it could prove to be an engaging documentary experience, something that many folks find to be pretty rare. I think it's definitely diverting, but in the context of the strongest recent docs it doesn't stand out all that much. B