ABC's Diane Sawyer, Julie Andrews take a look back at 'The Sound of Music'

"The Sound of Music" is celebrating half a century of song. In a primetime special on Wednesday night, ABC's Diane Sawyer takes a look back at the von Trapp family and the lasting legacy of this treasured classic.

They were going to call it "Love Song." And in fact, the two actors confess to Sawyer that a romance might have developed between Julie Andrews and Christopher Plummer.

Sawyer: "Did you have a crush on Christopher Plummer? He said he had one on you."

Andrews: "Yea, we sort of did. We were never an item, as they say. But now we are the best of friends."

Plummer: "We should've had a huge, smashing affair."

PHOTOS: See how "The Sound of Music" cast compares to the real life von Trapp family

But Andrews remembers herself being like Maria -- nave and unaware of her own romantic potential.

And on Wednesday night with Diane Saywer, she embarks on a journey back to those hills, that house, and the music that lives on.

Sawyer: "You have your memories."

Andrews: "I do! Oh my God, do I ever."

Memories of moments we all know so well.

"Just as we were about to shoot, the second assistant director come up to me and said, 'Can i just tell you something? The little one doesn't swim. So could you fall forward from the boat and get her as quickly as possible?' I said, 'Well, yes!' Of course I fell backwards, not forward, because the boat was rocking and you just see a pair of feet disappearing."

And memories of the moments viewers never saw.

Andrews: "We actually went up the mountain in big, open carts pulled by oxen."

Sawyer: "The tarp over your head, freezing cold, waiting for the clouds to part?"

Andrews: "I would sit on top of all the camera equipment and then they'd hoist me up and up we'd go."

Those hills aren't listed on any guide map. And you won't believe the lengths that they went to to get to that same exact spot.

You can watch the special Wednesday night on ABC7 at 10 p.m.