The former Friends star was pictured arriving at Heathrow Airport with fiancé Justin Theroux on a drizzly Wednesday morning (12 November).
Jen kept a low profile, hiding under a black hat and sunglasses, while Justin walked ahead with their luggage.
She'll be hitting the red carpet this evening for a screening of black comedy Horrible Bosses 2, the sequel to 2011's hit Horrible Bosses.
Jennifer resumes her role as sex-loving, dirty talking dentist Julia, with the sequel's plot seeing her land herself in a sex addiction support group.
In fact, Julia's so dirty talking it seems there was one line in the script that Jen absolutely refused to say!
"It was the one thing I didn't say! Imagine how bad it must've been if I had said, 'I can't say it'," she said. "Either it was so bad, or I just really didn't understand it, which was probably the case."
Aww, now we want to know what that was!
As Jennifer was accompanied to London by Justin, we're wondering if he'll join her on the red carpet tonight.
The couple became engaged back in August 2012 but have yet to set a wedding date, frequently saying they are happy with their relationship as it currently stands.
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