The button in this case is Button Blake, the young daughter of Janice and Dirk Blake who are going through a nasty divorce. After Janice refuses to let her soon-to-be ex-husband have Button for his two days of visitation, he takes her and puts her on his yacht, the Blue Nymph. It isn't a case of kidnapping per se and the judge in the case gives temporary custody to Roger and Lois Gray, friends of the family. Button is a young heiress having inherited $4 million from her grandfather and Perry Mason is the administrator of the trust. Keeping an eye on the girl aboard the yacht is Vince Rome who has been taking care of himself and hoping that Janice will marry him once the divorce goes through but she refuses. Vince has been asked by Dirk to find information he can use against Janice but Vince concocts a plan to blackmail either parent with the data he is fabricating. Dirk calls off Vince but in a fight Vince's gun goes off which is seen by a witness.
