The fact that there isn't a single likeable character in Cul de Sac does not diminish its artistic value in the least. Ageing, furtively kinky Donald Pleasence is married to sexy young Francoise Dorleac. The couple's hermitlike tranquility is shattered when wounded gangsters Jack MacGowan and Lionel Stander invade their home and hold them hostage. As Dorleac urges her tremulous husband to do something, the two criminals begin behaving in a fashion that can only inadequately be described as eccentric. Drawing upon two of Polanski's favorite themes-isolation and latent insanity--Cul de Sac actually improves upon each viewing, assuming that the viewer has the intestinal fortitude to sit through it once.
~ Hal Erickson, All Movie Guide