Meryl Streep knew she wanted to be in Rob Marshalls next movie.

She just didnt know what it was.

Rob knew that I wanted in on whatever it was he did next, Streep tells EW.

Mary Poppins Returns

Jay Maidment/Disney

I had no idea what he had in his head, says Streep.

Theyve lost their minds.

Streeps history withMary Poppinsis likely just like yours.

You know, I loved it.

But I wasnt familiar at all with the other P.L.

I didnt even know they existed.

Marshalls vision for unplaceably-accented Topsy and the film in general struck a chord with Streep.

The child in himnevergot put to bed.

Hes up all night, jumping on the bed and thinking of ideas and laughing and giggling.

Its not unlike the spirit of the original.

I dont know anybody else on Earth that could have done that except Rob Marshall.

And thats when I said, Okay.

This is a gift to the world.'

Its going to be amazing, Streep recalls thinking.

And you might kind of tell, you know?

Theyve got something really good under wraps until Christmas.

For more onMary Poppins Returns, pick up the new issue ofEntertainment Weeklyon stands now, orbuy it here.