Favreau shared the photo on Instagram on his 52nd birthday, Oct. 19, with the caption, "Birthday Surprise." By Saturday night, the image had been liked more than 110,000 times.
The two appear to be posing in a futuristic cantina, with a bottle of wine from Skywalker Vineyards, Lucas' California vineyard.
In the photo, Lucas is shining a light from his smartphone, leading one Instagram user, thedrumjedi, to comment, "Look at George lighting the scene and everything. Old habits die hard. Love that guy."
The Mandalorian is set in the time period in between Return of the Jedi and The Force Awakens.
"After the stories of Jango and Boba Fett, another warrior emerges in the Star Wars universe," an official summary from StarWars.com says. "The Mandalorian is set after the fall of the Empire, and before the emergence of the First Order. We follow the travails of a lone gunfighter in the outer reaches of the galaxy far from the authority of the New Republic."
The Mandalorian will air on Disney's streaming service, but an official date hasn't been announced.
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