Finally ready to work again after giving birth to her baby, Dr. Mike must lead a rescue party when Sully and Cloud Dancing are among the passengers on a train that has been overtaken by robbers and wrecked. Sully had negotiated Cloud Dancing's release from Army detention, and the two were taking the train to Colorado Springs when a gang of thieves derailed the train in an effort to rob it. Meanwhile, Dr. Mike must again face the prejudice against women doctors when she finds that the townspeople have become used to being treated by young Dr. Andrew Cook who filled in for her while she was on maternity leave. For his part, Andrew has become reluctant to return the practice to Dr. Mike and go back to Boston, as originally agreed.

Dr. Mike returns to work after giving birth to Katie, but has a hard time trying to balance her professional life, wifely duties, and being a new mother. Sully feels neglected.

Dr. Mike is charged with malpractice and must stop treating patients during the lawsuit, leaving medical matters to the young and reluctant Dr. Cook.

Colleen considers leaving college when the famous singer, Gilda St. Clair, offers her a job traveling the world with her.

Dr. Mike's attempts to befriend a Latin American woman are rebuffed; the Reverend Johnson searches for a teacher to take his place.

Dr. Mike faces the prospect of leaving her practice and friends for Wyoming when Sully is offered a job surveying Yellowstone National Park.

Dr. Mike is arrested and put in jail for treating a fugitive Indian; Jake and Preston run against each other for mayor of Colorado Springs.

A sick and ragged prospector wanders into town and Jake Slicker recognizes the man as his father, who abandoned him years before.

Dr. Mike, Sully and Matthew team up with a legendary marshal in order to nab the thieves who wounded Matthew during a bank robbery.

A severe storm bears down on Colorado Springs, disrupting the arrival of Preston Lodge II and Dr. Mike's attempts to prepare a Thanksgiving dinner.

Grace and Robert E. encounter fierce opposition when they attempt to enroll their son in the town's all-white school.

Dr. Mike desperately attempts to find out why patients are dying mysteriously after having been treated in her clinic. As Dr. Mike searches for the answer to why a deadly and mysterious infection haunts her clinic, the townspeople begin to fear coming in for treatment. Unable to find out what is causing the deaths, Dr. Mike then makes a fateful decision that could mean destroying everything she has worked for through the years. Meanwhile, the attraction between Colleen and Andrew grows while she is home from college for a visit.

As Christmas approaches, Brian questions his faith when he learns that Dr. Mike cannot save the sight of the Reverend.

In a case of mistaken motivation, a judge sends Sully to prison after he is spotted with criminals bent on stopping the construction of a dam.

Dr. Mike's Uncle Theodore, a concert pianist, sees in Brian not only a talented musician, but his own dead son.

Kid Cole and Sister Ruth visit Dr. Mike at a difficult time in their marriage.

When Colleen, who is working on a college paper, asks Dr. Mike to recall her most memorable case, Dr. Mike looks back on the five turbulent years she's lived and loved in Colorado Springs. As they sit with Andrew, who is mysteriously ill at the clinic, Dr. Mike reminisces about her tumultuous career -- its successes and its failures -- and realizes how many divergent cases she as seen and treated. When Andrew's condition takes a turn for the worse, Dr. Mike warns Colleen about the fine line between emotional involvement and professional detachment, an issue with which she has long struggled in the frontier town that's now her home.

An old friend of Sully's visits, wanting to financially help the family. Although he falls in love with Michaela.

While Sully is away for a few days to procure some money, Preston arrives threatening to repossess the homestead for nonpayment of the load. Daniel rejects Dr. Mike's objections and pays off the entire loan. Upon hearing how Daniel interfered in his business, the proud Sully becomes furious.

Sully, depite being wounded by two bank robbers, works to free his wife, Brian and Katie when they are taken hostage by the desperate men.

Brian takes a liking to visiting writer Walt Whitman, even when the townspeople shun Whitman over rumors of his alternative lifestyle.

Horace attempts suicide after his wife, Myra, leaves him, prompting Dr. Mike to send for her and their young daughter.

After Marjorie joins the Women's movement she blows into town stirring everyone up and has a fling with Loren.

Sully and Brian forge a true father-son bond when Brian's free-wheeling, irresponsible adolescent behavior puts him in mortal danger, and Sully disciplines him. As Brian's stepfather, Sully has let Michaela set the rules for Brian up to now. But when Brian's misbehavior with his friend Anthony puts them, and the town, in danger, Michaela and Sully realize that Brian needs -- and wants - Sully to act as Brian's real father and give the boy the boundaries he needs, which enhances and strengthens their bond.

After Cloud Dancing is beaten almost to death, Sully organizes an escape for him and the others on the reservation, which turns deadly. Sully flees with a price on his head.

Sully tries to get Cloud Dancing to safety in the north. The actions of the renegade dog soldiers take their toll on the town. An old enemy goes after Sully and Cloud Dancing.