Kiss of Death (1947)

In Henry Hathaway's definitive crime noir:

• the characterization of maniacal, cold-blooded, chuckling killer Tommy Udo (Richard Widmark in an impressive debut performance) with a nervous hyena-like giggle
• the frightening scene when Tommy Udo tied up elderly, crippled Mrs. Rizzo (Mildred Dunnock) (the mother of alleged informant Pete Rizzo) in her wheelchair with an electrical cord and laughingly shoved her down a long flight of stairs - and then sadistically chuckled to himself