Fluorescent Footprints



Rather than track by means of conventional detective skills, the character uses something akin to Aura Vision to track the footsteps of their prey. Even on surfaces or terrain that would never show their passing otherwise, or where their tracks would disappear into those of a crowd. The Empath may even be able to tell the emotional and physical condition of the person being tracked by the color of their footprints.

Robots and characters/animals with Super Senses can get in on this too by using infrared sight to track the heat left in their prey's footsteps. Here the downside is that in extremely hot environments it's useless, or if too much time passes.

This is usually because of the Rule of Perception: if the trail didn't light up, it wouldn't be visible to the audience. The Scarily Competent Tracker usually has their tracking and/or Super Senses depicted this way.

Film

 * In a deleted scene in Tron: Legacy, Rinzler uses this to determine the heroes fled on a Light Train.

Live Action Television

 * The TV series V (the eighties version) had a Visitor use this technology in a fold-down eyepatch to track La Résistance members.

Video Games
"Ethereal Whispering Voice From Nowhere: "Follow me!""
 * On tailing missions in Assassin's Creed II and Brotherhood you can turn on Eagle Vision to have a glowing trail appearing after the target you're trailing. There's also the mystical red footprints in modern day Monterriggioni in Brotherhood. The red trail is
 * Word of God states that the footprints in modern day Monterriggioni were simply put there to lead lost players back to the hideout; the red color (which led to some Wild Mass Guessing by fans) was simply an oversight.
 * Batman: Arkham Asylum displays clues this way in Detective Mode.
 * Agent Norman's ARI in Heavy Rain highlights the footprints this way.
 * In the Metal Gear Solid series, footsteps can be seen this way with the aid of thermal/night vision goggles, notably in MGS4, where there is an entire segment based on following footsteps this way.
 * In Psi Ops the Mindgate Conspiracy, Aura Vision allows you to see footprints leading to secret rooms and secret messages.
 * "Senses" mode in X2: Wolverine's Revenge. See the world through Wolverine's enhanced senses, which includes glowing footprints, smells, and mines.
 * The Trace biochip in The Journeyman Project.
 * One quest in Dragon Quest VII requires the heroes to Invoke this by collecting some glowing moss and spreading it on the feet of a monster so that they can track it to its hideout.
 * A variation exists in the Mount and Blade series -- in the world map, tracks of NPC parties are depicted as bright arrows, giving more information on the party leaving the tracks on mouseover (the information available depends on your or yoour highest-skilled party member's tracking skill).
 * Doom 3:


 * In My Sims Agents, your magnifying glass has the power to make regular footprints (amoung other things) that would otherwise be rendered invisible into highly visible, colorful trails for you to follow.
 * Duke Nukem 3D level "Rabid Transit": in a certain area, you can use your night vision goggles to see big bearpaw footprints (that lead you to a secret). The message "TELLTALE FOOTPRINTS" also becomes visible nearby.

Real Life
When walking or driving, you actually warm up the ground a little bit as you pass by. An infrared camera can actually pick this up. Googling for infrared footprints can get you a lot of examples.