Judging by the number and variety of heart emojis on an iPhone, there are countless ways to say “I love you.” Finn, however, expresses it the old-fashioned way: drawing one by hand, albeit on his mother’s phone. The crooked heart drawing takes on a life of its own in Haddix’s tale, becoming a symbol of the resistance movement in the alternate world. Finn’s heart epitomizes a child’s love for his mother, but it also serves as a counterpoint to the manipulative tactics of the authoritarian government, symbolizing love as a tonic for evil. Also, since the authoritarian regime uses technology as a tool of repression, it is appropriate that the heart is a symbol rendered by hand. A child’s expression of love signifying resistance to oppression is a resonant narrative device.

Digital devices play an important role in the plot’s development. Kate’s letter is stored on her laptop. Messages are sent via text. Natalie uses her phone for research, communication, and navigation. The mere discovery of Kate’s phone left in the house is a signal that something is amiss. Despite the fanciful notion of parallel universes and intrepid kids on adventures, the novel acknowledges the reality of the digital world.