6x3 - 3rd Rock from the Sun

Dick and Mary decide to go on a double date with Sally and Don, but things start to become uncomfortable when Dick and Sally begin talking incessantly about how good their other half is in bed. The next day Dick and Sally come to realize that neither Mary or Don said anything about how good they are, and immediately worry that they aren't. Meanwhile, in a food store, Mary and Don run into each other and, consumed by what they'd heard about each other in bed, share a kiss. Elsewhere, Harry and Tommy follow in the footsteps of Jack Kerouac and take to the open road.