SAN DIEGO - Ok, so about that Meryl Streep headline...I can explain.

In Rian Johnson's upcoming sci-fi thriller "Looper," Joseph Gordon-Levitt (in his second outing with the director after the 2005 noir throwback "Brick") stars as a contract killer who assassinates targets sent from the future by a shady corporation. One day, the target turns out be an older version of himself, as played by Bruce Willis.

Which is why when I spoke with Gordon-Levitt and his co-star Emily Blunt at a Comic-Con press line for the film, I thought it would be interesting to ask Blunt which older actress she would choose as the future version of her character.

"Helen Mirren," chimed in Gordon-Levitt, eyeing his co-star as though trying to picture her as a 60-year-old woman.

"Meryl as well, though," said Blunt. "Oh my god, that would be so cool!"

(Note: What would've been funny here is if I'd asked her "Meryl who?" with a dumbfounded expression, though I'll admit it's probably better that I didn't.)

"Sorry I pigeonholed you as a Brit," said Gordon-Levitt, apologizing for his presumptive answer.

Responded Blunt: "Come on! She can do accents!"

Fun, right? I thought so.

Interested in hearing why Gordon-Levitt loves working with Rian Johnson? Curious to know which era both actors would travel back in time to if given the chance? Well, what are you waiting for? Click on the video above to watch the full interview!

"Looper" comes out on September 28.

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