C. Robert Cargill

Cargill, along with Derrickson and Jon Spaihts, worked on the script for Marvel's film Doctor Strange (2016).

Both Cargill and Derrickson returned as writers for Sinister 2 (2015), which was directed by Ciaran Foy.

Having wanted to be a fiction writer from a young age, Cargill considered every film he reviewed and its feedback as a learning experience. According to an interview with The Austin Chronicle he compared it to "a strenuous, endless crash course—maybe even a master class—in what does and doesn't work in a story." The idea for his first film came to fruition when he met up with a fan and friend Scott Derrickson at a bar in Las Vegas where he pitched his idea for Sinister. Derrickson, showing great interest in this concept, contacted producer Jason Blum who particularly liked the simplicity of the concept and understood the urge to make it as fast as possible before it could be made by anyone else. Shooting of the movie started in September 2011, 6 months after and was first screened at South by Southwest. In an interview with Film.com, Cargill stated that his days as a film critic were over for the time being due to his success and dedication to his new-found career path. "I may pop in every once in a while and write up reviews, but ever since I was a child, I’ve wanted to be a fiction writer, and now I have the chance to do it in both formats that I am in love with."

On the 26th of February 2013, Cargill released his first novel, Dreams and Shadows, an urban fantasy story of folklore and mythology, which also follows three modern characters from childhood to adulthood.

Cargill wrote his first article in 2000, when he volunteered to write a review of the movie Crouching Tiger, Hidden Dragon for a website called "Guerilla Films." His article managed to get the highest amount of traffic of over 50,000 hits, "a HUGE deal" at the time, which secured him the job to write more reviews. While working for Guerilla Films, Cargill began spending time with Ain't It Cool News' Eric Vespe (AKA 'Quint' on the site), which landed him a job on Ain't It Cool's "Indie Indie Column," a previously abandoned post. During his work as a blogging critic, Cargill met various directors, which occasionally led to small roles in independent productions. Besides his work for Ain't It Cool News and his involvement with Spill.com, he also did freelance work for Film.com and Hollywood.com (the site that owned Spill.com).

Christopher Robert Cargill (born September 8, 1975) is an American screenwriter, novelist, podcast host, and former film critic known under the pseudonyms Massawyrm (on Ain't It Cool News) and Carlyle (on Spill.com). Cargill currently resides in Austin, Texas with his wife.

Both writers are also working on a movie adaptation of the Deus Ex video games. Cargill and Derrickson will also team up to write the script for The Outer Limits, a movie based on the influential 1960s television show of the same name. The film, produced by MGM, will be adapted from a single episode of the classic show, "Demon with a Glass Hand."