Trimble began to write adventure fiction, and sold an animal story to a New York magazine in about 1908. In 1909 he visited Vitagraph Studios in New York while doing research for a series of articles called "How Movies Are Made". As he chatted with the sole assistant working under Rollin S. Sturgeon, head of the scenario department, he learned that a story of special interest to producer Albert E. Smith had been set aside because it required a dog that could act—not simply do tricks, but to behave naturally on command. Trimble scanned the script and said he could train any dog to do what was needed.