Morgan!

Morgan: A Suitable Case for Treatment is a movie starring David Warner, Vanessa Redgrave, and Robert Stephens. After his wife leaves him for his former best friend, a failed London artist begins his descent into madness in trying to...
Morgan, an aggressive and self-admitted dreamer, a fantasist who uses his flights of fancy as refuge from external reality, where his unconventional behavior lands him in a divorce from his wife, Leonie, trouble with the police and, ultimately, incarceration in a lunatic asylum.