The morning after, four's a crowd.
Peter and Samantha still live together despite taking a break in their relationship. They have an agreement that they can see other people and even bring them home if the opportunity presents itself, with the guest room to be used for such purposes. On the morning after a wedding that they both attended, they find that each has brought home 'a date'. It isn't so much that fact that bothers them, but who each has brought home which causes an issue. This experience makes both Peter and Samantha reevaluate their relationship status.
