When characters do something significant in a location - for example, camp there for the night or murder someone - they inevitably leave some evidence that they've been there. Sometimes, these pieces of evidence can reveal not only the fact that they were there, but when
Once the evidence is found by someone, they can then deduce that whoever has left it must be nearby.
Warmth in any form is a big giveaway, and so is smoke - from a cigarette, a stamped-out campfire, or a gun.
In Real Life
, this is sometimes called "tracking and trailing".
[[folder:Film - Animated]]
- When the trio of Sid, Manfred and Diego arrive at the human camp in Ice Age, Diego remarks upon a piece of kindling: "It's still green. They broke camp less than two hours ago."
[[folder:Film - Live Action]]
- Raiders of the Lost Ark. At the beginning of the movie Indiana is leading an archaeological expedition in the Peruvian jungle. They find a dart and one of the bearers, Satipo, tastes the tip.
Satipo: The Hovitos are near. The poison is still fresh, three days. They're following us.
- In Young Frankenstein, when the main trio follow mysterious violin music into a secret room, they find a cigar smoldering in an ashtray.
- In Beethoven's 2nd, as the family is tracking their pet dogs, they happen to find some dog poo that likely belongs to one of the dogs. To find out when they left it there, the daughter sticks a finger in it to feel if it's still warm. It is.
- In the film version of No Country for Old Men, Sheriff Ed Tom Bell is investigating Llewelyn Moss' trailer and notices condensation on a bottle of milk. The killer they're tracking had left the milk there less than an hour ago. Unfortunately, this doesn't really help them find the killer now.
Ed Tom Bell: Now that's aggravatin'.
Ed Tom Bell: [points to a bottle of milk] Still sweatin'.
Wendell: Whoa, Sheriff! We just missed him! We gotta circulate this! On Radio!
Ed Tom Bell: Alright. What do we circulate? "Lookin' for a man who has recently drunk milk?"
- The Peacemaker: Colonel Devoe realizes their bomber just left because the breakfast eggs are still warm. In fact, the bomber went down one elevator just as his team was going up the other.
- In Megamind, Megamind and Roxanne go into Metroman's hideout and find a glass of water with ice in it, which is proof that someone was there recently. Sure enough, they turn around to find Metroman still living there.
[[folder:Live Action TV]]
- Invoked in "Suitable For Framing", an episode of Columbo. The killer puts an electric blanket over the body in an alibi trick, so that the body would still be warm when the police arrives.
- The Twilight Zone episode "Where is Everybody?". A man finds himself all alone in a deserted town with a case of amnesia. While he's exploring a police station he finds a lit cigar smoldering in an ashtray. When he looks in a cell he finds a sink with the water running and shaving equipment (including a brush with wet shaving cream) sitting around. All of this is evidence that someone was there not too long ago. The Twilight Zone Twist is that he's actually in a hallucination caused by isolation. Watch it here.
- A couple times on The X-Files, a still-burning Morley cigarette left on the ground or in an office ashtray indicates that the Cigarette-Smoking Man has been there recently. Since he's The Chessmaster who's far from careless, he most likely deliberately left these there.
- In the very last shot of the last scene of the last episode of Now and Again, the government goons sent after Michael Wiseman and his family get there just in time to see the breakfast still on the table and the back door swaying.
- In the Elementary episode "Snow Angels" a Federal Reserve cash processing facility is robbed during a blizzard. When they find the tracks left by the robbers' vehicle, Sherlock is not only able to determine how long ago they were there from the fact that they can still see the tracks when it's snowing two inches an hour, but what kind of vehicle they were driving.
- Dungeons & Dragons module CM1 Test of the Warlords, adventure "The Ruins of Alinor". The PCs find a cave filled with the bodies of dead giants and wolves and a fire with venison cooking over it. From the condition of the bodies and the roasting meat, the PCs can deduce that the attack occurred within the last half hour and that the perpetrators are probably nearby.
- Call of Cthulhu supplement, Terror Australis adventure "Old Fella that Bunyip". The Investigators may stumble upon the scene of one of the Bunyip's attacks. They find a picnic site with signs of a struggle and a tea kettle of water heating over a fire. The kettle is still whistling, which means they arrived minutes after the attack.
- A popular myth about the disappearance of Mary Celeste is that when she was discovered, there were cups of tea on a table, still steaming hot.
- In the third Jack French game, there are some still-smoking cigarettes in the ashtray when Jack gets to a crime scene. This is used to show that the murderer was there minutes ago, and provides a clue to his identity - Vince, the police officer who alerted you about the murder.
- Guards from The Elder Scrolls IV: Oblivion will sometimes say "the body's still warm... The murderer cannot be far away." They will do this even when they are the one who killed the victim, or when you killed him in front of them.
- In an episode of Sharky And George, the two enter the local diner and find it deserted. In keeping with the show's Film Noir parody, they observe that a plate of food's still hot, so everyone must have left recently.
Indices: Just in Time
, Crime and Punishment Tropes