When it comes to describing someone who is intensely focused, there are a number of synonyms that come to mind. One possibility is "concentrated," which implies a single-mindedness and a deep immersion in a particular task or activity. Another option might be "absorbed," which suggests a complete absorption in what one is doing and a lack of distraction or interruption. "Engrossed" is another synonym that captures the sense of being fully engaged and invested in a task, while "fixated" connotes a level of fixation or obsession with a particular activity or goal. Other possibilities might include "attentive," "involved," "dedicated," or "devoted." Overall, there are many different ways to describe someone who is intensely focused, and the best synonym will depend on the specific context and situation.