Murder by Decree (1979)

Sherlock Holmes investigates the murders committed by Jack the Ripper and discovers a conspiracy to protect the killer.

From memory:  Stolid and pedestrian Sherlock Holmes mystery has good production value and Plummer and Mason are well cast as Holmes/Watson, but the large ensemble of stars could have been put to better use.

Halliwell (no star): "Interminably long and unpardonably muddled variation on this over-familiar theme, with halts for the performances of guest star and no clear grip on narrative or character."

Maltin***: "Involved, often lurid story doesn't sustain through conclusion, but flaws overshadowed by warm interpretations of Holmes and Watson by Plummer and Mason."

Showdown (1973)

Two men who have been friends since childhood find themselves on opposite ends of the law.

Standard Western with two aging stars and a wee touch of melancholy.

Halliwell (no star): "Routine star Western adequately done."

Maltin**1/2: "Agreeable but unexceptional Western yarn was Seaton's final film."