William Boyd made his screen debut as Hopalong Cassidy in Hop-ALong Cassidy. He was really William known as Bill Cassidy when he does arrive, but he gets wounded in a gunfight and limped a bit for the duration of the film. The guys in the bunkhouse called him Hopalong after he gave himself that nickname. Throughout the rest of the 66 films and TV shows we rarely heard his Christian name.
The plot is a standard western one, an outlaw gang stirs up a feud between the Bar 20 and a neighboring outfit owned by Robert Warwick. But it takes Bill Boyd to come up with the solution, aided and abetted by James Ellison whom he acquires as a sidekick.
Gabby Hayes is in this as Uncle Ben and he's the usual Gabby Hayes. He proved so popular that Paramount just resurrected him for the next few years before he left the series. Here as the chief villain guns him down it shows the Saturday matinée kids just how dastardly he is. Rather stupidly he leaves him to bleed out rather than finish him off. I guess Paramount did not want to shock the kids whose dimes to see the film and the subsequent series planned.
So Hopalong Cassidy becomes an American institution. Curiously enough Bill Boyd did a few non-Hoppy films after this before settling down into this character permanently.
It was a good beginning for an American institution.