Despite a frankly nonsensical plot full of formula antics and an unnecessarily protracted running time, Let's Do It Again is a healthy reminder of the relative verve, energy and talent to be found nowadays in the so-called 'black exploitation' film—a somewhat loaded term considering the fact that no one ever speaks of 'white exploitation', and particularly inappropriate in relation to such a high-spirited yet unassuming entertainment as this. Modestly directing himself as a straight man for much of the time, Sidney Poitier gives most of the show over to the ebullient Bill Cosby, and the latter takes every advantage of the opportunity…. Working with such a patently ludicrous intrigue, Poitier for the most part keeps things moving lightly on the strengths of his enjoyable cast, with a nicely handled chase thrown in for good measure. But a few happy moments are occasionally offered by lines in Richard Wesley's script. Threatening the absurdly named Biggie Smalls over the phone while pretending to be a big-time Chicago operator, Billy Foster … offers the following challenge: "I understand you're six feet and good-lookin'—how'd you like to be four feet and ugly?"
Jonathan Rosenbaum, in his review of "Let's Do It Again," in Monthly Film Bulletin (copyright © The British Film Institute, 1976), Vol. 43, No. 511, August, 1976, p. 166.