Once dubbed "Dentist to the Stars" by George, Whatley is a recurring character, and appears as Jerry's dentist.
In "The Yada Yada", Whatley converts to Judaism, and Jerry expresses to Whatley's Catholic priest in a confession his belief that Whatley has done this solely for right to make jokes (which offends him, not as a Jewish person, but as a comedian). Also in this episode, Kramer coins the phrase "anti-dentite".
Whatley briefly dates Elaine. He is also from New Jersey.
In "The Mom & Pop Store", Jerry is unsure of whether or not he is invited to Whatley's party based on the way Whatley says, "Why would Jerry bring anything?" to Elaine. George also takes a pencil to the party because he thinks there will be a lot of dentists there and he wants to ask if they can compare the teeth marks on a pencil he found in the Jon Voight car to see if he really was the previous owner.
Whatley was labeled as a "re-gifter" in the episode "The Label Maker", when he gives a label maker to Jerry as a gift because Jerry gave him Super Bowl tickets, when Elaine realizes that it's the same label maker Elaine had given to him as a gift for not charging her for dental work.
In "The Strike", Whatley gave out Christmas gifts that were actually donations made in their name to a charity. This leads George to conjure up a fake charity called "The Human Fund", and he gives out fake Christmas gifts. Also, at Whatley's party, Jerry meets Gwen. Gwen is a "two-face", looking very pretty in some environments, but not so much in others.