Leonardo DiCaprio & Mark Ruffalo March for Climate Change

Leonardo DiCaprio goes undercover while participating in the 2014 People’s Climate March on Sunday (September 21) in New York City.

The 39-year-old actor was joined by Mark Ruffalo, and Edward Norton and Evangeline Lilly were also reported to be there as well.

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The march, which calls for drastic political and economic changes to slow global warming, was organized by a coalition of unions, activists, politicians and scientists.

The day before, Leo was named the new UN Messenger of Peace and received a special certificate to mark the honor.