For the sixth entry in M-G-M's popular seven-film 1943-1951 Lassie series, the beloved and courageous collie appropriated another dog's tale and made it fully her own. Screenwriter William Ludwig (who'd penned the previous Hills of Home and The Sun Comes Up) skillfully adapted Eleanor Atkinson's 1912 novel Greyfriars Bobby, based on the true story of a devoted Skye Terrier in 1860s Edinburgh who became legendary for guarding his owner's grave for over a decade, as a compelling, custom-fitting Technicolor® Lassie vehicle. Her costars were already familiar to fans: Donald Crisp (as Lassie's big-hearted, ill-fated sheepherder-owner), Edmund Gwenn (as the pubkeeper who champions the battle to stave off the dog's destruction as a stray), Reginald Owen, Alan Napier, Arthur Shields, Lumsden Hare and others had shared screen time with the charismatic canine before. When this dog gets her climactic day in court, clearing a legal hurdle more formidable than any prior natural or medical perils, Challenge to Lassie's verdict is an uncontested triumph.