"I want to hear you heart," she tells Don. "Oh, I think it's broken."
"You can hear that?" Don says, somewhat shocked that the hippie woman who was dabbling in fortune telling tricks might have actually stumbled upon some truth.
But she was only referring to the stethoscope: "I can't hear anything. I think it's broken."
Don is undeterred. Loitering outside Sylvia's apartment, Don hears a song outside her apartment that sings, "I must think of a way into your heart." It inspires Don to return to the office to work on a pitch, not for Chevy, but for Sylvia to take him back.
But when he returns to his apartment to woo her he discovers the police and the robbery that happened while he was gone. He passes out, probably because of the speed. But he assures Sally later that it wasn't a heart attack.
That doesn't mean his heart isn't broken; he is the world's greatest pitch man and he knows this, telling Ken that to sell Chevy, "the timbre of my voice is as important as the content." His pitch to Sylvia, however, has fallen short.
A song closing out the credits sums up his defeat: "Words of love, so soft and tender, won't win a girl's heart anymore. If you love her then you must send her somewhere where she's never been before. Worn out phrases and longing gazes won't get you where you want to go."
As an aside, the "Inferno"/hell theme reappeared, with Stan telling the creative team he has 666 ideas. And the elevator is still stage for a telling scene between Don and Sylvia – it appears to be Don's vehicle of choice as he moves through the circles of his hell.
One also wonders if Peggy was not offered the speed injection or if she simply just turned it down. It is suggested this was a practice at CGC, and Peggy has been game to smoke marijuana with the boys before. Either way, she had some words of wisdom for Stan who, after trying to kiss her, tells her of his 20-year-old cousin dying in Vietnam.
"I've had loss in my life. You have to let yourself feel it. You can't dampen it with drugs and sex. It won't get you through," she says.
It's advice Don Draper should take as well.