The 35-year-old actor, who played one of Samantha's love interests on the HBO hit series, is part of an ongoing effort to feature more attractive male stars and increase romance on the ABC show, Zap2it.com reported.
On the new series, Lewis will play a man named Chad Barry who begins a romantic interest for Kevin Walker, one of the lead characters in "Sisters."
The Web site said that the episode that will introduce Lewis, entitled "Sexual Politics," will air after the drama returns from its upcoming holiday break.
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