The Licker of the Resident Evil film series is very similar to its game counterpart. The key difference between them is that when the film version of the Licker feeds on living flesh, it mutates into a stronger form.
In the first film, an unknown number of Licker bio-weapons were being produced within The Hive, a massive underground lab complex controlled by the Umbrella Corporation. How precisely they were created is unclear, though it is hinted that they may have been produced by injecting the T-virus into live rabbits.
When Umbrella sends in a special ops team to shut down the Red Queen, the AI controlling the Hive, the operation goes awry when the team are attacked by the zombified staff. Some of the specimen containers within "Dining Hall B" are damaged and one Licker is awakened, ripping its way out and running loose within the complex. The survivors are unaware of the Licker until near the end of the film when the creature ambushes treacherous Umbrella operative Spence Parks and kills him, feeding on his body and mutating into a stronger and faster form. The creature's body grows in size and its muscle tissue expands and hardens further; its lower jaw also splits into a jagged pair of mandibles and it grows bony plates on its back.
When Alice and the last few survivors are aboard the escape train, the "Uber-Licker" boards and rips open the front carriage, killing Chad Kaplan and wounding Matt Addison. Alice fights the creature but bullets fail to harm it; luckily Matt manages to open a service hatch in the deck and the Licker falls through, its tongue tied to a grating and so it is dragged along the tunnel tracks at high speed. The friction from scraping the tracks sets the Licker on fire and Alice closes the hatch, severing the tongue and leaving the monster to burn on the tracks.
Resident Evil: Apocalypse
Umbrella re-open the Hive to find out what happened down there, but in doing so they release all of the infected workers and other creatures sealed within. At least three Lickers also escaped and as Raccoon City descended into chaos, the creatures roamed free.
When Raccoon police officers Jill Valentine and Peyton Wells, along with weather reporter Terri Morales, took shelter within a church, they found themselves boxed in with the Lickers and a horde of zombies waiting outside the front door. They were saved by the timely arrival of Hive survivor Alice - now enhanced with superhuman abilities - who managed to kill each of the beasts singlehandedly.
Resident Evil: Retribution
In the fifth film of the series, the Red Queen - now in control of all of Umbrella's remaining assets - has been producing Uber-Lickers within Umbrella Prime, the corporation's primary bio-weapon testing facility. These Lickers are slightly different from the Uber-Licker within the Hive: they do not have lower mandibles, they have two tongues and their bodies are as large as Land Rovers. They are much stronger than their predecessors, being able to easily crush prey as much as rip them apart. They also seem to be capable of producing organic pods similar to cocoons and can preserve victims inside them for later consumption.