Izzie is so over Alex. That's because Katherine Heigl's sweet intern finds love on
Grey's Anatomy (Sundays at 10 pm/ET) with returning heart-transplant patient
Denny Duquette (played by Jeffrey Dean Morgan) instead. Well, at least for a
nine-episode arc chronicling Denny's quest for two hearts -- Izzie's and a new one
for himself.

"I'm there to shake things up a little bit," Morgan says. His wealthy marine-biologist
character departed on the Jan. 15 episode without a desperately needed transplant.
Disappointed, Izzie thought that was goodbye.

Grey's Anatomy fans won't see Denny for at least a few episodes, but when he does
return, Morgan promises pulses will quicken. "Izzie [gives him] a whole new reason
to live," says Morgan, whose character believes it was love at first sight with the
beautiful doctor. "It's going to be really interesting how it plays out. There's great
chemistry."

One doctor who doesn't appreciate their chemistry is Alex Karev (Justin Chambers),
Izzie's ex-squeeze. "I would anticipate confrontation," Morgan says. "Denny isn't
going anywhere, and Alex isn't going anywhere.... Neither of them wants to let
Izzie go."

Fighting for Izzie's heart is keeping Morgan a very busy man. In addition to his
role on Grey's, he plays the phantom-fighting father on WB's Supernatural and
Mary-Louise Parker's deceased husband (who appears in flashbacks and dream
sequences) on Showtime's comedy series Weeds.

Shooting Grey's Anatomy in Los Angeles and Supernatural in Canada doesn't leave
much time for Morgan's off-screen romance with actress Sarah Lancaster (she was
Ephram Brown's love interest, Madison Kellner, on Everwood). "It's tough right
now," he says. "The minutes I use on my text [messages]! Lots of I-love-you's back
and forth." But the actor is grateful for the opportunity to return to Grey's Anatomy.
"I can't remember ever being on a show where everyone is so damn happy to be
back," he says. "The atmosphere is amazing."