Whitta was the screenwriter of The Book of Eli (2010), co-wrote After Earth (2013) with M. Night Shyamalan, and co-developed the story for Rogue One (2016).

When ACE closed down in 1992,[2] he became deputy editor of The One for Amiga Games and was involved with founding the original PC Gamer magazine[3] in the UK.

He was hired to script the first Star Wars stand-alone film, Rogue One, directed by Gareth Edwards.

[14] On 27 October 2016, Variety reported that Warner Bros., Village Roadshow and Team Downey had put together a writers' room for the third of the Guy Ritchie Sherlock Holmes movies, with several top names, including Whitta, Nicole Perlman, Justin Malen, Geneve Dworet-Robertson and Kieran Fitzgerald.

Whitta is also the writer behind a popular short series of comic books based on the Death, Jr. character, together with cover artist Mike Mignola and illustrator Ted Naifeh.

[21] Having been extended to a second three-part series,[22] the writing has received praise as "charming and cleverly subversive"[23] and for its "quirky characters and slick humor".

Whitta continues to chair the Octoberkast charity event every year, creating the "Space Rocks" game in 2013.

The show has featured several celebrity guests, including Elijah Wood, Brie Larson, and Danny Trejo.

Whitta resides in the San Francisco Bay Area, California with his wife Leah, and has two children.