We finally decided on the theme earlier. I had thought we had already decided on this last month, but they both ended up changing their minds. I wasn't too excited about the previous idea of hide-and-seek. Besides the blatantly obvious game (which neither child really understands the concept of), I was having a tough time thinking of other activities.
The new spy theme makes for easier planning. Especially since there is a specific TV show that they think of when they hear "spy".
. . . I may have deliberately influenced their decision by humming the song as they tried to think of a theme they both like and agree on. Who says Jedi mind control is just fiction?