JR's Inside Out project has been going on for two years total, inspiring people around the world to establish their identities in their local communities. It's simple: you email your portrait to JR, he sends back the print, and you paste wherever you want.

Thanks to director Alastair Siddons, the progress and highlights of Inside Out have been compiled in a documentary that premiered earlier this month at the TriBeCa film festival. TONIGHT ONLY, the whole world gets to see the result of their hard work on HBO at 9 p.m. EST.

In the video below, Alastair and JR discuss their decision to document "Inside Out" and how it grew beyond their expectations. Additionally, they share how they were able to pick the stories highlighted in the documentary. Whether you know about JR or not, this project is a spectacular place to familiarize or re-familiarize yourself.

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