When Dr. Inga Halvorsen, a visiting Swedish surgeon, arrives, Hawkeye is at his most flirty. He escorts her to the V.I.P. Tent, carrying her suitcase. Winchester tries to horn in, but goofs when he makes a crack about how "lumpy" older Swedish women can get. Realizing he's made a horrible faux pas, Charles excuses himself, leaving Hawkeye and Inga to laugh together.
When Inga, in OR, demonstrates equal if not superior surgical skills than her male counterparts, it irks Major Winchester. It also annoys Hawkeye - who had tried to make seemingly well-received romantic advances on her - at least at first. When she corrects Charles in another surgical operation, the embarrassed and even more irritated Charles is forced to eat crow, sheepishly and somewhat sarcastically thanking her, then fuming about it to Hawkeye.
Hawkeye, at first put off by Inga's sexual aggression, discovered in The Swamp she was just as romantically assertive as he can be. in talking to the angry, complaining Charles, he realizes how much of "an ass he's been" in his own attitude towards her. In the end, Inga earns the respect of both Winchester and Hawkeye, with whom she finally spends a romantic evening, even sharing a tender kiss before she leaves camp.