In the various mystery sub-genres, suspects shadow, spy upon and track the detectives at least as often as the investigators stake them out. Yet roleplayers react to being watched with less sang froid than do their fictional counterparts. Like imprisonment, enemy surveillance falls into the category of plot elements that players resist, because they seem to deprive the group of choice. If you can’t take an action because you fear your powerful foes will catch you at it, you feel hemmed in—a sensation adjacent to, if not really analogous to, the dreaded railroad. Yet plots can turn stale if the bad guys never come after the heroes. To use Antagonist Reactions, adversaries have to know enough about the investigative team to strike out at them.
Fight this tendency by giving players a sense of agency over the extent to which the bad guys watch them. Remind them that Infiltration applies even when they’re not technically sneaking into a particular location. Any action undertaken at any point in the investigation can be obscured by the same set of skills that let them creep into bank vaults, server farms, or underground cannibal hideouts.
In some games, like Trail of Cthulhu, Infiltration is called Stealth. This slightly different framing may do much of the work for you.
Don’t just let the players stew in the thought that the bad guys have every means of locating them and anticipating their moves. Give them opportunities to overcome surveillance techniques, presenting them as obstacles to be knocked down with successful Infiltration tests. Pose the problem and let the players, after you’ve suggested they use this ability, propose the specific solutions.
GM problem: You notice the security camera on the nightclub wall turn toward you as you pass by.
Player solution: I note the locations of all the cameras on the street and attempt to plot us a course through their blind spots.
GM problem: A couple of ill-complected sailors stand on the docks of Thalarion, clearly watching you.
Player solution: I call attention to myself, trying to lure them into an alcove, so the others can get the drop on them. Then we’ll find out who put them up to this.
GM problem: When you boot up your laptop, the camera light goes on for a split-second.
Player solution: I set up a bot to generate false search activity, and hide what I’m really doing under a fractal firewall pattern.
Successes in evasion needn’t completely derail all enemy action against the heroes. That would be boring. But it can delay it, or leave the visiting henchmen at a disadvantage when they do arrive to mess matters up.