Dr. Timothy Stryker

Because otherwise, you know, you have to start looking for excess cortisol, excess aldosterone.

He built a successful endocrinology practice.

And a family in a quiet Boston suburb.

Striker's wife of 14 years, McHale, says her husband has shown no signs of violence.

And she'd probably know what to look for.

She's a psychotherapist.

He does present this very cool exterior, very flat, very unemotional, very in control, which makes you wonder what's going on behind the front, behind the facade.

Do you think you know?

That might be one reason he decided to become a doctor.

I just knew it from a very young age, that's what I wanted to do.

You know, because it's my nature to want to help people.

It was one thing he had in common with Lynn Goudy.

She had so much dynamic energy.

And she was, by all accounts, driven.

She earned top honors in high school and eventually went to medical school while working as a medical technician.

She was a successful OB-GYN, specializing in high-risk pregnancies.

She loved what she did.

Paula Dennett is a nutritionist who worked closely with Dr. Gowdy.

Lisa Zolot was one of Dr. Lynn Goudy's patients who noticed right away that there was something special about her.

On a routine visit, Dr. Gowdy had a sense that Lisa's unborn baby was in danger.