At the height of the '60s sexual revolution, upwardly mobile married couple Bob (Robert Culp) and Carol (Natalie Wood) returns from a freethinking group encounter session with an elevated sense of honesty. So when Bob tells Carol he's had an affair, his newly liberated wife happily accepts the news. Before long they're both experimenting with new partners and sharing their sexual escapades with best friends Ted (Elliott Gould) and Alice (Dyan Cannon). Soon they too join in on the hedonistic lifestyle, until both couples agree to swap wives with each other, a decision these friends may or may not be ready to make.
