S1·E6 Firefall

A series of mysterious deaths plague the life of conductor Ryder Bond. In each case, the victim is incinerated by supernaturally hot flames. As Kolchak investigates, he finds out that an arsonist, Frankie Markoff, was a fan of Bond's, and was killed in a penny arcade. His funeral procession crossed Bond's car, allowing the spirit to become a ""doppelganger"" and try to take over Bond's life. Each victim was burned to death when they fell asleep, and if Bond goes to sleep the doppelganger will take him over for good. Fighting sleep himself, Kolchak must exhume Markoff's body and reunite it with his restless spirit before he too bursts into flame.