Atta Boy Luther!

The Ghost and Mr. Chicken (1966)

In the first and funniest film of his 5-picture deal with Universal, Don Knotts plays Luther Heggs - a meek type-setter who in his quest to become an ace reporter agrees to spend the night in a spooky mansion and becomes a local hero.

Vic Mizzy's peppy (and creepy) score adds to the brilliance of the film.

character actor sightings:

• Jesslyn Fax and Nydia Westman as the bickering boarding house ladies.
  
• Reta Shaw plays the banker's wife and head of the local occult group.
• Charles Lane and Ellen Corby show up in the courtroom scene
• Philip Ober as villian Nicky Simmons (was the real life hubby of Vivian Vance until she divorced him in 1959)
• Hope Summers ("Clara") and Hal Smith ("Otis") are brought over from TVs Mayberry as similar characters in the first scene of the film.
• Bert Mustin plays the old man boarder who lends Luther his flashlight.

trivia: Don Knotts personally contacted the makers of Bon Ami to get permission for a running gag where the product is mentioned. The other running gag has an off-camera wiseacre yelling "Atta Boy Luther!" in every crowd scene. Knotts said in his autobiography that the voice belonged to screenwriter Everett Greenbaum.