Sandman (Flint Marko) is a fictional character who appears in comic books published by Marvel Comics. A shapeshifter endowed through an accident with the ability to turn himself into sand, he eventually reformed, and became an ally of Spider-Man.
In "Spectacular Spider-Man", Marko is taken to an undisclosed location. Hammerhead tells him that the Big Man has had his eye on Marko and wants him for a special job. Gullible, Marko is riveted with the prospect of meeting the Big Man in person, but Hammerhead tells him no one meets the Big Man. Marko is then taken inside, where he's strapped and hooked to a machine by Dr. Otto Octavius. He is then told that he will be infused with millions of microscopic silicon granules, creating sub-dermal silicon armor and making him impervious and undetected to scanners. During the proceeding, Marko morphs into sand and bursts, seemingly dying.
However, Marko is able to reassemble himself almost back into his human self, but he is not happy with the results and starts hammering on the one-way window. Hammerhead addresses him as "Sandman" and tells him to calm down. While being escorted out, Marko manages to reshape his entire body back to normal. .Hammerhead tries to play Marko against Spider-Man, but Marko is not so much interested in revenge as in getting rich. So he disregards Hammerhead instructions, dubs himself Sandman and leaves to rob the Midtown Bank. He walks in through the front doors, takes the money, the alarm goes off, and burst out from where he came in. Outside, Spider-Man is waiting for him, but, as Sandman, Marko is overconfident and takes on Spidey with his powers. He proves to be an opponent to be reckoned with. Sandman inadvertently slips the Big Man's name, and then takes off to rob more banks, but neglects to take the loot he had just robbed.
He goes on a crime spree across town, robbing ATM machines and banks with relative ease. When he hijacks an armored car, Spider-Man takes him on again. The ensuing fight drives the car out of control and they crash into a construction site. Sandman shows Spider-Man how his webbing is useless on him and buries him under girders. Sandman maintains the upper hand during most of the fight. However, his overconfidence eventually gets the best of him, and Spider-Man manages to bathe him in concrete. Sandman is instantaneously solidified.
He is eventually taken into prison where he is incarcerated in a cell designed to release air pressure if he tries to escape. At some point, Doctor Octopus makes contact with him, probably through the Vulture who was working as a trustee, and gets in on a plan to break out and take down Spider-Man. On the day of the escape, the Vulture brings him a sandwich, and Sandman berates him, saying he only can only ingest raw silicones. The Vulture then informs him the escape is scheduled for that night. When the time for the breakout comes, Electro overloads the power generators of the prison, shutting down Sandman and Rhino's cell. Then Sandman releases the Enforcers and everyone make a run for it.
On the next day, Rhino goes on a rampage in Times Square, calling Spider-Man's attention. When he shows up donning the black suit, the rallied super villains make and entrance and attack the webslinger. When Spider-Man realizes they are too much to handle, he retreats into the sewer. Sandman, Shocker and Doctor Octopus go after Spider-Man, but Sandman asks to be excused as the contact with water is turning him into mud. Shocker insults him so he pursues the search.
After the hunt comes to naught, the Sinister Six celebrate in a restaurant in anticipation to Spider-Man's defeat. The group soon starts quarreling over their personal interests, until Electro takes a stand claims that they must trust Doctor Octopus so that everyone can get what they want.
Then, so as to lure Spider-Man, the Sinister Six take hostages in a bank near Central Park. The plan succeeds and Spider-Man arrives only to be ambushed and quickly subdued. Unbeknownst to them, Spider-Man was being controlled by his black suit, which fights back on its own and a battle endues. Sandman is repeatedly foiled and is finally overpowered when Spider-Man uses Shocker's gauntlet to disintegrate him and keep him from reforming. After the Six are defeated, the police take them into custody.
Sandman is thrown back to Ryker's Island where he stays until he is somehow extricated by the Master Planner. He joins the mysterious benefactor's new Sinister Six to make another attempt to kill Spider-Man. The Master Planner employs a new tactic this time: teaming the villains in pairs to as to wear Spider-Man down. Sandman is paired with his old buddy, Rhino, and the two attack Spider-Man in a tire barn, after he had neutralized Electro. They toss Spider-Man around for a while but are lured to the docks. Sandman decides he wants to unmask him before delivering the final blow, but Spider-Man evades and goes after a fire hydrant. He cracks it open, soaking Sandman until he becomes mud. Sandman manages to recover and goes after Spider-Man, but the night air starts freezing he water in his body, saturating his silicones and thus making him slower. Upon realizing this, Spider-Man lures Sandman into being covered with snow, freezing him completely. The Tinkerer eventually extracts him at the behest of the Master Planner.
After the Master Planner's plan comes to naught, Sandman is loaded out to Hammerhead. He robs a jewelry store to fence the goods, but Spider-Man tries to foil him as usual, and the two fight. Sandman is forced to retreat empty-handed as the police arrive. He begs Hammerhead for another chance and is sent to steal the Urn of Morpheus from a museum. However, as the alarm goes off, Spider-Man shows up. Sandman asks him how he always intercepts him while doing a job, and wonders if he has some kind of "spider sense." Sandman hides himself in a room filled with statues, posing as a stone ornament. When Spider-Man passes by unsuspecting, Sandman attacks and ensnares him. He tries to suffocate the webslinger but Spider-Man is able to break free. He also notices how Sandman has grown bigger, and the super villain explains that while in prison he learned how to absorb silicones, thus enhancing his powers. Spider-Man calls him pathetic, saying that he could do something good with his powers, but instead wastes them on crime. Sandman stands down and wonders if he can be a real hero, but as soon as Spider-Man lowers his guard, he strikes him. Sandman sneers and bursts out with the stolen good.
On the next day he meets with Hammerhead on Rockaway Beach to collect his payment. Some kids were making sandcastles there, and as they taunt a little girl for her work, Sandman forms a real size castle in from on them, scaring the bullies away. The little girl thanks Sandman and he tells her to go home because it's getting late. Hammerhead witnesses this act of kindness and taunts Sandman for being nice to little girls. Sandman protests claiming he only wanted to torment the teens. When he finally gets his severely reduced fee, Hammerhead explains that his payoff got cut down after the Big Man and the Master Planner collected their shares. Sandman was aspiring for a big score, so Hammerhead suggests he hijacks an oil tanker, which would secure a big payoff.
Sandman absorbs massive amounts of sand and takes on the taker with ease. Spider-Man steps in and the two fight. Hammerhead's henchmen start draining the tanker, but Sandman chases after Spider-Man, neglecting the purpose of his job. In the ensuing fight, he rips the tank open, spilling oil over the sea. Then he inadvertently sparks the tanker ablaze. Sandman grabs Spider-Man who tries to warn him of the collapsing tanker. He thinks that's a trick but when he realizes what had done, he lets go of Spider-Man and takes the tanker's crewmen to safety. Sandman claims he didn't intend for that to happen, and then grabs Spider-Man and hurls him away to safety. Just when the tanker is about to explode, Sandman grows into an even bigger size and encases the tanker. He takes the full impact of the explosion, which turns his body into glass. Spider-Man assumes he died, but Sandman slips away intact, looking pleased with himself.
In "Ultimate Spider-Man", Flint Marko was a prisoner who broke out of prison. After breaking out of prison he got into a nuclear accident which gave him the ability to control, and morph into sand at will. During a rampage in New York, Nick Fury captured him and dumped him onto a island surrounded by water so he could never bother or hurt anyone ever again.
In the "Spider-Man" movie trilogy, Flint Marko stole money to pay for medical treatment for his terminally ill daughter, Penny. While on the run from the police after escaping from prison, he accidentally falls into an experimental particle accelerator that molecularly binds him with sand, giving him shape-shifting sand abilities. A major focus of the plot involves Marko's connection to the murder of Ben Parker, Spider-Man's uncle, in the first film. Sandman is later spotted by police officers walking down the streets of Manhattan. Sandman gets on top of a dump truck filled with huge amounts of sand. When one of the policemen climbs atop the truck, he is assaulted by a huge fist made out of sand. Having absorbed the truck's sand to add to his mass, a giant Sandman then emerges. The police shoot at Marko, but he manages to escape by turning into a sandstorm and flying away with the wind. At the Spider-Man fair, the sandstorm is spotted, and Spider-Man goes to investigate. In doing so, Spider-Man confronts Sandman, foiling his attempt to rob an armored truck, but Sandman gets away. Later, at the police station, it is revealed by Police Captain George Stacy that there is evidence implicating Marko as Ben Parker's killer, and he also tells Peter and May that the carjacker, Dennis Carradine, that Peter confronted two years earlier was really Marko's accomplice, and did not fire the shot that killed Ben Parker. In the meantime, Sandman robs a bank, and Spider-Man, now with enhanced abilities due to his new black suit, chases him to the subways. During their fight, Spider-Man bursts a water tank, flooding Sandman in water and turning him into mud, which is swept through a sewer grate. Believing that Sandman is dead, Spider-Man leaves; unbeknownst to him, however, Sandman, who is washed out to the river, is able to eventually reconstitute himself.
Spider-Man later tears the symbiote off his body in a bell tower after learning of its parasitic nature, and it merges with Eddie Brock, to become Venom, who convinces Sandman to team up with him to destroy Spider-Man. Sandman agrees because he feels that Spider-Man will not stop chasing him until he is dead. The two kidnap Mary Jane Watson and take her to a construction site, forcing Spider-Man to face them both.
During the fight, Sandman uses the site's sand to again increase his size, turning into a version of himself several stories high. After Venom restrains Spider-Man with his webbing, almost strangling him, Sandman nearly beats Spider-Man to death, but for the intervention of Harry Osborn, under the guise of the New Goblin, who comes to his friend's aid with his Goblin arsenal. Harry explodes a pumpkin bomb at Sandman, and then distracts Venom enough to free Spider-Man. Working together, the two manage to save Mary Jane, defeat Venom, and temporarily disable Sandman. (Harry and Brock are both killed in the process). Sandman returns to his normal size, and having discovered Spider-Man's real identity, he reveals that he never wanted to kill Uncle Ben. He had been trying to ask to use Uncle Ben's car, and accidentally shot him in a moment of panic. Realizing that Marko is telling the truth, Spider-Man forgives him. Marko is touched by Spider-Man's compassion, and he shapeshifts and flies away.