Deputy Seraph was an unfinished pilot for a television series in 1959 featuring the Marx Brothers: Groucho, Chico, and Harpo.
The brothers played Harry and Nick, two inept robbers who try to pull a jewelry heist wearing Groucho Marx disguises.
Encouraged by the audience reaction, in April the brothers began filming a pilot for Deputy Seraph, a proposed weekly TV series in which Chico and Harpo were angels whose job was to possess people for brief periods of time: bringing two lovers together, exposing a criminal, and so forth.
A psychiatrist attributes the pianist's strange habit of shooting the piano keys and speaking in an impossible Italian accent to various childhood traumas (these predilections, of course, were Chico trademarks).
[1] All that remains of the pilot episode of Deputy Seraph is about fifteen minutes of raw, unedited footage, available at the Marx Brothers website.