“Inferno” is episode eighteen of season two of Mutant X.
The Double Helix is looking for the unique heat signature of a mutant firestarter who’s killed three people so far. A hooded figure in an individual is setting fire to a building with his powers. Outside, a fire marshal calls it in, saying he thinks he’s got a fix on the firebug. He’s told to wait for backup but says there’s no time and heads in.
The Double Helix has picked up the fire. They land and Shalimar waits outside; ferals have no liking for fire. Emma stumbles across the fire marshal inside, who is trying to put out the fire with a totally inadequate extinguisher. He yells at her to get out, then a pile of burning crates falls on him. Emma goes to find him; he’s been badly burned. They take him out of the fire and Emma helps with the pain. The marshal is talking about his wife and Emma sees glimpses from his life. She sees him walk towards a light, then he dies. She tells the others she thinks she died with him.
At Sanctuary, Shalimar looks unhappy and Emma asks if she’s okay. Shalimar feels she should have done more help. Emma says that Shalimar was the only smart one. Civilians shouldn’t walk into a fire, especially one like that. There was nothing that could have been done and nobody should have been in there except fire professionals. Shalimar asks if Emma can hear herself – because that had a lot of technical stuff in it. Jesse tells Adam that the dead man, Ray Larkin, was the lead fire investigator of these attacks. Brennan checks on Emma, who claims she’s fine. Though she now has a determination to catch the arsonist. Shalimar is trying to get over her fear of fire.
Emma wants to go see Ray’s widow. Brennan asks why; they have Ray’s office files. Emma says Ray kept more at home, and her reasoning for that is not very solid. He may have talked to his wife about the investigation. Adam asks how they go in; Emma says she and Brennan will go in as journalists. After Emma leaves, Brennan speaks to Adam about her. She’s acting odd and it’s not just grief. Adam tells him that’s why Brennan is to keep an eye on her.
At Ray’s house, Emma knows the doorbell doesn’t work. They claim that they are doing a memorial piece on her husband. A work colleague of Ray’s, Frank Sanders, is there. He’s not impressed with them and it seems he’s already been through Ray’s files without finding anything.
The widow, Lisa, says Ray was obsessed with this case; whoever the arsonist was, he could just make fire appear. She thinks Emma sounds just like Ray when Emma talks about the pattern. Lisa thinks Ray was onto something that morning. And Emma seems familiar to her. Emma asks to take photos of the house and is staring into a mirror when she sees Ray in the reflection. She raises her hand and the mirror breaks. Then Ray’s younger brother arrives, and Emma knows he’s called Billy.
Jesse has found no connection between the fires. Adam suggests some hands-on investigating and Shalimar volunteers. After all, the place has already burned down. She arrives at the building to find Frank looking around. Shalimar looks on as Frank finds a watch engraved with a graduation date from the firefighters’ academy, and pockets it instead of placing it into evidence. She then confronts Frank and claims she’s from the insurance company. And makes insinuations to Frank that maybe he knows more than he’s letting on.
Emma finally admits that she saw Ray in the mirror. The connection seems deeper than that, though; she seems to have Ray living inside her. Frank Sanders seems like a suspect – a fire marshal who has perhaps got too obsessed with fire – but he also seems too obvious.