Unforeseen: when a movie about people LITERALLY writing a dictionary turns out to be captivating, specially the further it strays from the actual dictionary-writing. "The Professor and the Madman" features Sean Penn and Mel Gibson both retaking characteristics from some of their better-known, pre-controversy roles, with Gibson going back to the "Braveheart" Scottish accent and Penn to the "Dead Man Walking" maybe-redeemable inmate murderer; resulting in a very strong on-screen chemistry.
By the time this movie is released in most markets, its fame will likely stem from its legal issues which lead to Mel Gibson basically disavowing it and director Farhad Safinia doing so in full (the movie is credited to "P.B. Shemran", an Alan Smithee-like alias if there's ever been one). I find this decision suprising as for most of the film I could have easily bought this as a Mel Gibson-directed work. As a filmmaker, he might not have the strongest of auteurial signatures, but said signature that can most easily be defined in the depiction of gore, a fascination with language and Christian faith elements (most obvious in "The Passion of the Christ" and "Hacksaw Ridge"), definitely makes an appearance here.
Not content with Gibson-like directorial decisions, the screenplay fortunately digs deeper into some topics than any Gibson script has. Penn's character's arc in particular is well-developed in creating empathy towards the mentally ill, which is still not common enough nowadays, nevermind in a time when phrenology was still a valid study. The word "redemption", so rare yet supposed to be the most Christian of virtues as well, gets a very strong definition with this character arc. Obsession is touched upon as well, not to Aronofsky-an levels, but still enough to be worthy of a mention.
Considering the unforeseen depth of the treatment of these topics, it's truly unfortunate that there are some cases where the movie relies of the most shallow of tropes to force tension. The worst case of this is the almost-mustache-twirling-villain characters, with no depth or motive beyond antagonizing and foiling our brave heroes. One case in particular is not as tragic when a (until then) well-developed and rounded character inexplicably takes that villanous turn, at least having given us a solid base before. Additionally, the visuals suffer with some establishing shots clearly having made with inferior digital video quality, creating a jarring effect that takes you out of the movie. All in all, despite these shortcomings, "The Professor and the Madman" is a worthy story that goes into unanticipated and fortuitous depths, intensities, profoundities.