John Edward Szeles (September 9, 1958 – February 22, 2022), better known by the stage name The Amazing Johnathan, was an American comedian and magician. His act was mostly composed of hijinks, interaction with one specific audience member, and a few legitimate magic tricks. From 2001 to 2014, he was a year-round headliner in Las Vegas. Self-described as the "Freddy Krueger of Comedy", Szeles performed wearing his ever-present headband, and his shows frequently used gore; for example, pretending to suck on his own hanging eyeball, cutting his wrists, and skewering his own tongue. He was also good friends with fellow performer Criss Angel and helped him perform a variety of illusions, most notably during three guest appearances on Angel's Mindfreak.

Szeles was born in Detroit, Michigan, the son of Doreen and Edward Szeles.[3][4] In the 1970s, he relocated to California, where he began his career performing on the streets of San Francisco.[5] He first appeared on television in The 8th Annual Young Comedians Show in 1983 and later went on to become the host of the short-lived 1991 syndicated variety/game show Ruckus. He appeared on various talk and variety shows from the mid-1980s to mid-2000s. His only credited performance as an actor was "The Obligatory Holiday Episode" of The Weird Al Show (playing the part of Uncle Johnathan). He made several appearances on Late Night with David Letterman, a record 24 appearances on Fox's Comic Strip Live, and had several specials on Comedy Central including Comedy Central Presents, Lounge Lizards, and more recently his own one-hour special entitled Wrong on Every Level. He dedicated the special to his Uncle Eugene, who showed him his first card trick which "started this whole mess". He appeared in the 2005 documentary The Aristocrats.

Johnathan had success in Australia following appearances on Channel 9's Hey Hey It's Saturday.

Szeles also authored a how-to book on practical jokes titled Every Trick in the Book, a compilation of both classic practical jokes and plain magic tricks, along with his own original material in both categories. From 2014 onwards, he was working on his memoirs with the working title of Drive It Like You Stole It, although his declining health prevented him from finishing it.

Szeles died in his sleep of heart failure at his home in Las Vegas on February 22, 2022, at the age of 63