The circus coming to town impacts William and Hester's relationship in a few ways.
1. William is excited about the circus coming to town, while Hester is less enthused. This creates a bit of tension between the two, as William tries to get Hester to see the circus as a fun event, while she remains skeptical.
2. The circus coming to town also provides a distraction for the couple, as they are forced to deal with the influx of people and animals into their small town. This puts a strain on their relationship, as they are both pulled in different directions.
3. However, the circus also brings them closer together, as they have to rely on each other to get through the chaotic week. In the end, the circus brings out both the best and worst in their relationship, but ultimately strengthens it.