Damien Gavin Lewis (born March 1966) is a British author and filmmaker who has spent over twenty years reporting from and writing about conflict zones in many countries. He has produced about twenty films.

He has written more than fifteen books, some of which have been published in over thirty languages. His books have appeared on bestseller lists in many countries. He is a Fellow of the Winston Churchill Memorial Trust and a Fellow of the Royal Geographical Society.

Lewis worked as a war correspondent, and between 1991 and 2005 he wrote, directed, produced and filmed a number of documentary films for National Geographic, the BBC, Channel 4 and Discovery, amongst others, largely focusing on investigating and exposing environmental and human rights violations in Africa, the Middle East and Asia.

In 1991 Lewis's independently-funded documentary film Parks or People?, about conflict between rainforest conservationists and indigenous tribes in the Congo, won the Wildscreen Film Festival Golden Panda Award.

In 1998 he created a documentary film for the BBC, Hidden Cost of Heroin, exposing how heroin is traded for wildlife on the Burmese border. This film won at the BBC One World Awards.

In 2000 Lewis's documentary film Death in the Air, about the use of chemical weapons in the Sudanese civil war, was a finalist in the British Rory Peck Awards, but its accuracy was disputed by the London-based European-Sudanese Public Affairs Council.

In 2004 Lewis wrote his first book, Slave, a novel which won the Index on Censorship Book Award at the Index on Censorship Awards. The book was later adapted as a film, I Am Slave, which won the Drama Award at the BBC One World Media Awards in 2011. Slave was also adapted into a stage play: Slave - A Question of Freedom, by Kevin Fegan, produced and directed by Caroline Clegg and Feelgood Theatre Productions. It won Best Stage Production at the inaugural Media Awards 2011 in association with the Human Trafficking Foundation, and Best New Play at the Manchester Evening News Awards.

In 2005 Lewis's documentary War Hospital produced by CTV Television Network and the National Film Board of Canada, about International Committee of the Red Cross doctors working in the world's largest field hospital in Sudan, won the Best of the Festival Award at the Columbus International Film & Video Festival.

Lewis has written other fiction and nonfiction books. In 2006 he was chosen as one of the "Nation's Twenty Favourite Authors" by the UK Government's Quick Reads Initiative in association with World Book Day.

In February 2018 Lewis became a patron for the Scottish charity Bravehound which provides assistance dogs for veterans.