Smallville: Season 4, Episode 17

Onyx (13 Apr. 2005)

TV Episode  |  TV-PG  |   |  Adventure, Drama, Romance
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Ratings: 8.7/10 from 457 users  
Reviews: 6 user

An experiment with heated (black) kryptonite at Luthorcop causes an explosion which badly wounds Dr. Sinclair, the scientist in charge, and creates a molecular copy of Lex which has the ... See full summary »



(character created by: Superman), (character created by: Superman), 6 more credits »
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Title: Onyx (13 Apr 2005)

Onyx (13 Apr 2005) on IMDb 8.7/10

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Episode cast overview:
Jason Teague (credit only)
Dr. Sinclair
Craig Lapthorne ...
Security Guard
Carra Maureen ...
Fencing Instructor


An experiment with heated (black) kryptonite at Luthorcop causes an explosion which badly wounds Dr. Sinclair, the scientist in charge, and creates a molecular copy of Lex which has the evil side of his personality. While the real Lex shows Clark the experiment was to create far stronger crops, the evil one gives Sinclair a fatal injection in hospital after questioning him. Fearing an effect on himself, 'Evil Lex' locks the good Lex up wearing an iron mask and sets out ruining lives in Smallville, such as closing The Talon when Lana refuses to be his girlfriend, and taunting Lionel Luthor badly enough to make him turn away from charity. When Chloe shows Clark proof on hospital video recordings there must by two Lex's, Super-boy is duped into telling the fiend everything, believing him to be the real one, so the Clark family and Chloe become his prime targets, and he knows about green kryptonite and its affect on Clark. Written by KGF Vissers

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Release Date:

13 April 2005 (USA)  »

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Did You Know?


In wine cellar scene Evil Lex tells Clark he wants him to remember that he was the one man who beat him. This is a reference to The Dark Knight comics in which Batman defeats Superman and tells him to remember him as the one man who beat him. See more »


Lex Luthor: I gotta hand it to you guys. I mean, keeping something like this a secret must've required an impressive ability to obscure the truth. Maybe the Kents and the Luthors have something in common after all.
See more »


Featured in Smallville: Blank (2005) See more »


I Drive Alone
Performed by Esthero
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User Reviews

Lex Luthor... meet...Lex Luthor
10 October 2007 | by (United States) – See all my reviews

Michael Rosenbaum shines in one of his best performances of the show. When an experiment with black Kryptonite goes haywire, Lex is split in two. One good and one evil. However, the question is which is the REAL Lex?

Rosenbaum cuts loose as the evil Alexander Luthor! A foreshadowing of what Lex's future could hold, Rosenbaum portrays the darkness inside of Lex to perfection and doesn't hold back. The only thing that could have made this episode better was if legendary Lex Luthor, Gene Hackman guest starred.

Plot: 9 Acting: 10 Special Effects: 8

Episode Rating: 9

4 of 4 people found this review helpful.  Was this review helpful to you?

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