For about the first two thirds of The Landlady's Pet ( that's the real title, by the way - The Star Boarder was the former title, but ultimately it was changed) it seems that it is going to come across as three distinctly separate parts - the first third, where Charlie is the "star boarder," the landlady's favorite lodger to the chagrin of her jealous husband, the drunken scene, and the obnoxious son's disruptive magic lantern show.
But as soon as the lantern show begins it becomes clear that it is going to tie the rest of the film together, which is something that Chaplin wasn't doing much during that first year making Keystone short comedies for Mack Sennett. The drunken scene is sort of a straggler, it doesn't seem to have any reason for being there other than that Chaplin can do it so well (so well, in fact, that Robert Downey Jr. included it as part of his performance in the phenomenal 1992 film about Chaplin's life), the conclusion of the film and the tying up of loose ends is a welcome surprise.
Watch for Gordon Griffith, a mainstay in Chaplin's earliest films, stealing the show as the landlady and her husband's obnoxious son. It's easy to see why Chaplin kept casting him in his films!