Todd Masters makes mutants.

More precisely, his character effects shop — L.A.- and Vancouver-based Mastersfx, which creates practical and digital makeup effects and animatronics for film and TV — provided prosthetics for the mutants in the CW’s “The 100,” which debuts its third season on Jan. 21.

In the post-apocalyptic drama, only those humans living in space stations survive nuclear Armageddon on Earth. When 100 return to the planet’s surface to test its habitability, they discover that not everyone died during the holocaust; many became mutants, including some of the flesh-eating variety.

While Zoic Studios does CG work for “The 100,” Mastersfx handles the practical effects. “We do all the show’s weird stuff,” Masters says.

The speed at which TV effects are created can be breathtaking. “Depending on when we see the script, we sometimes have to turn things around in two-and-a-half weeks,” he says. “It’s pretty outrageous.”

Over its 28-year history, Mastersfx has made a reputation for itself as a quick-turnaround effects house for such shows as HBO’s “Six Feet Under,” Showtime’s “Dexter” and ABC’s “Grey’s Anatomy.” It has emerged as a go-to shop for television effects, which often face greater time constraints than movie effects.

“TV likes us,” says Masters. “We’ve gotten used to the nutty pace.”