Bargemen save a homeless man from drowning in the Seine, but the police soon discover this man, who been living under a bridge, had been beaten prior to being thrown in the river. Maigret investigates this attempted murder, but there few facts and fewer witnesses to consider. The man is in the hospital in a coma. Why would someone want to kill this man? Why does anyone kill anyone? Motives for murder are limited, so of them what might apply here--apply to a nameless man living under a bridge?
"Maigret and the Tramp," the novel upon which this episode is based, is, for me, one of the more enjoyable George Simenon "Maigret" novels. As you read through the novel or as you watch this film two distinct threads begin to merge: Maigret considers the accounts given--the-what-happened-when-sort-of-thing--and he searches for the nameless man's past. Eventually the nameless man becomes known and the witnesses accounts merge, and Maigret knows what happened and why. The conclusion is typical Simenon.
This is a great episode in the Bruno Cremer "Maigret" series and one I can highly recommend. The casting seems perfect. A comment I often use to describe Simenon's mysteries and several episodes in this series is that the best parts are the lingering moments in-between beginning and end. Here, though, the ending--the last 5 - 10 minutes--may be the best part.