One particular theme can be Everyone faces coming of age, but each person handles it differently. In the story, Bryon changes from the beginning to end. At first, he cares only for himself and Mark. However, after he meets Cathy, M&M’s sister, he falls in love with her. As the story progresses, Bryon opens his heart to others. As he puts it: “I had quit thinking only about myself.” This is further shown when M&M runs away. As Bryon comforts Cathy, devastated over the loss of her brother, he says that “it was the first time I’d ever felt bad for anyone except Mark.” This realization marks his own coming of age, his path into maturity.
Bryon also changes in that he begins to recognize consequences for his actions. In the beginning of the story, Bryon really needs a job, but can't figure out why he hasn't gotten one. He blames everyone else, saying that they refuse to hire him. Yet later he realizes what the problem was all along and asks himself, “Who’s going to hire a mouthy kid who acts like he already knows it all?” Bryon's maturation involves a “haircut, clean clothes, and a really big change in attitude.” Bryon is aware of his transformation, and allows himself to continue on the path to maturity.
Yet he is also aware that Mark is not making the same changes. As Byron grows and learns, Mark desperately tries to cling to the gang life that they enjoyed as kids. Mark misses the camaraderie and sense of belonging that came from the extended family of the gang. Although Bryon tries to get Mark to see that it is good “when you know your own personality so you don’t need the one the gang makes for you,” Mark still searches for the relationships they had years ago. He continues to sell drugs, even though it hurts those around him. His concept of right and wrong only covers himself-he doesn't have room for anyone else in his worldview.
The story "That was Then, This is Now" is about the friendship of two boys, Bryon and Mark. They are very close while growing up. Mark's parents die and he becomes Bryan's foster brother. After Bryon's mother has surgery, they meet a girl named Cathy. Bryon and Cathy date. Bryon finds out that their friend Charlie has been drafted and is supposed to go to Vietnam. Mark and Bryon get mixed up in a deal with two Texans they are trying to hustle. Charlie tries to help them out but gets killed. For Bryon, Charlie's death is a wake-up call. He gets a job and stays out of trouble. He is maturing.
Cathy and Bryon have another friend named M&M. Bryon finds out that Mark has been selling him drugs. M&M is very messed up. Bryon makes the decision to turn Mark in for selling drugs. He knows he was connected with M&M's downfall. Mark is sent away for five years to a boy's reformatory. Mark gets out hardened and angry. Bryan tries to communicate with Mark, but he says to him "That was then, this is now." Eventually Mark goes to prison. Bryon is left to wonder if Mark could have turned out different.
The theme of the story is about maturity and change. Bryon changes after he grows up, but Mark seems to stay trapped in time. He has difficulty not getting into trouble which leads him to a life in prison. It is also about the theme of loyalty versus doing what is right.
In some ways this book parallels with the story "Twenty Years" by O'Henry.
The plot of That Was Then This is Now is when Byron matures and changes. He eventually makes a regretful decision of reporting Mark to the Police