This Thursday, American Idol will feature lots of familiar faces, but two of them are going to be truly special to longtime fans of the series.

According to TMZ, the series finale is going to featuring an appearance at the top of the show by original co-host Brian Dunkleman. In addition, viral sensation William Hung will be singing at some point during the broadcast.

J. Lo will perform brand new single on American Idol series finale.

In addition to Dunkleman and Hung, former judges Simon Cowell, Paula Abdul and Randy Jackson are also expected to make appearances, as well as many of the show's top 3 contestants over the last 15 seasons.

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