This short Harry Langdon comedy has an interesting setup that comes off pretty well. It also provides a good showcase for Langdon's distinctive comedy style, since it places his character in quite a variety of situations.
The story starts when, in the midst of a very unusual situation, Harry runs into an old Army buddy (Vernon Dent), and the two spend "All Night Long" recalling some of the events and escapades that took place in France when they served together in the war (World War I), with their memories played out in Langdon's characteristic style. Most of it works, and there are some good gags.
Langdon liked to play his characters rather differently than did the more familiar comedy greats of the silent era. For anyone who enjoys the silent comedians of the 1910s and 1920s, it's worth seeing a couple of Langdon's features just to get an idea of the different approach that he represents. There are times when he overdoes his child-like style, but he generally makes good use of settings and props, and he had some good writers, including a young Frank Capra, who wrote for this and several of Langdon's other films.