engross

To capture someone's attention so completely that they become oblivious to their surroundings. It suggests a state of deep immersion, where the mind is entirely occupied by a single activity or subject.

Unlike 'interest,' which can be passive, engrossing implies an active, absorbing force. While 'fascinate' emphasizes the charm or curiosity of the object, 'engross' emphasizes the total consumption of the person's mental capacity.

Typically used in contexts involving intellectual or creative pursuits—such as reading a gripping novel, solving a complex puzzle, or being lost in a project. It carries a neutral to positive connotation, though it can imply a neglect of other duties.