ABC's long running medical television drama 'Grey's Anatomy' is scheduled to return for its 12th season this fall, but fans will certainly miss Patrick Dempsey's Dr. Derek, who will not be on board for the first time.

According to Christian Today, Dr. Shepherd was killed off in 'Grey's Anatomy' Season 11 and now the network as well as series creator Shonda Rhimes is said to be in search of a well-known actor in his 30's to 40's to replace Dempsey. It is presumed that the new actor will also be Dr. Meredith Grey's (Ellen Pompeo) new love interest.

The report says that even though Meredith is the main character of the series, if some rumors are to be believed, even she may not be in the series following the upcoming season. Fashion Style claimed that 'Grey's Anatomy' Season 12 may possibly concentrate on the character's Alzheimer's with a view to allow Pompeo exit 'Grey's Anatomy.'

In 'Grey's Anatomy' Season 9, fans saw Grey was found to be positive when they were undertaking a test for Alzheimer's. It was then said that she inherited the gene from her mother, who also suffered from Alzheimer's disease until she died in Season 3 of the show. Since then, fans saw Meredith contemplating about the possibility of being suddenly affected by Alzheimer's.

The report in Fashion Style further states that Rhimes has confirmed that Season 12 will not be the final season of the series. Nevertheless, Pompeo's contract will be ending with this season and unless she signs for an extension, it is likely that the writers would kill off the character by focusing more on problems owing to her ailment.

If the report turns out to be true, 'Grey's Anatomy' Season 13 would be without Dr. Grey if not the show creators do a time-jump and bring in Meredith's children as the new interns of the show, to help the story come full circle.

'Grey's Anatomy' Season 12 will premiere this fall.