Most actors will go their whole career and never experience 14 seasons.

Its a blessing many in the cast didnt think would ever happen.

In fact, fellow original Chandra Wilson kept her day job into season 2.

SARAH DREW, BETSY BEERS (EXECUTIVE PRODUCER), KELLY MCCREARY, JASON GEORGE, KEVIN MCKIDD, JESSICA CAPSHAW, KRISTA VERNOFF (EXECUTIVE PRODUCER), CHANDRA WILSON, CATERINA SCORSONE, SHONDA RHIMES, ELLEN POMPEO, DEBBIE ALLEN (EXECUTIVE PRODUCER), JAMES PICKEN

Paul Hebert/ABC

I was like, Oh no, what do I do now?

I hadnt planned on being in L.A. not working and had to go back to New York.

I said, Okay, I learned from that.

I basically flew back and forth.

I came to work and went back home on the weekends.

Your show is doing very well, youre not coming.'

Im not such an introvert as I was anymore, Rhimes says.

I think Ive grown a lot as a businesswoman and as a leader.

Ive learned how to enjoy it and Ive stopped thinking its going to go away.

Rhimes certainly shows no signs of slowing down, either.

How many shows get to do 300?

Everything that can be implied by the number 300, should be implied, Capshaw says.

Its not something I ever expected that I would have in my life.

Whats wonderful is that its such a collaboration, Scorsone says.

We get to go in and play, and do our bit.

It really is a company of players and its greater than the sum of its parts.

Its an honor to be part of it.

Those ghosts include patients who look likeoriginal Fab Five membersCristina (Sandra Oh), George (T.R.

Knight), and Izzie (Katherine Heigl).

But those originals wont be the only ones mentioned over the hour.

Executive producer Krista Vernoffincluded an Easter egg huntthat will honor the beloved characters who have since left the show.

And certainly Merediths late-love Dereks (Patrick Dempsey) presence will also loom large during the hour.

There are definitely some echoes of my brother, Scorsone teases.

Theres a situation that happens that has some similarities to a situation with him.

Greys Anatomys 300th episode airs Thursday at 8 p.m. With reporting by Abby Stern