This week on the CW's Smallville, the DC Comics spellcaster known as Zatanna (guest star Serinda Swan) works her magic at Chloe's birthday party, granting the guest of honor a most special wish. As a result, Chloe is planted into her cousin Lois' body, and that switcheroo makes for one freaky Thursday.

In this exclusive clip, watch as "Chlois" — aka Erica Durance channeling Allison Mack, nervous lower-lip bites and all — beseeches Zatanna to use her "hex appeal" to undo what's been done. Plus: Does Clark have a wish of his own to make?

Coming Thursday: My feature Q&A with Serinda Swan.

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