S1E11 · Indian Summer

Complete story — includes the ending

Adam hangs himself in his hotel room after mailing a personal box to Don. In the wake of his heart attack, Roger returns to Sterling Cooper, but suffers a second heart attack during a meeting with the head of Lucky Strike, Lee Garner, Sr. As a result, Don is given a partnership in Sterling Cooper, making Pete jealous. Peggy is asked to write copy for a weight-loss device that vibrates, and discovers that it provides sexual stimulation; Don is impressed by Peggy's presentation and gives her a raise and a day off. Don and Rachel continue their affair, while Betty becomes increasingly sexually frustrated as Don's focus remains elsewhere. After receiving a visit from an air conditioning salesman who tours the house, Betty finds that she is sexually stimulated by the vibrations of her washing machine, and has a vision of sex with the salesman. Don calls Dr. Wayne to discuss Betty's progress, and Dr. Wayne suggests moving her towards psychoanalysis. While sitting in Don's office at the end of the day, Pete gets mistaken for Don and is given Adam's package by a mailboy.