In October 1969, FDNY firefighter Frank Sullivan (Dennis Quaid) dies in a warehouse fire, leaving behind his wife Julia (Elizabeth Mitchell) and six-year-old son John. Thirty years later, in 1999, John (Jim Caviezel), now an NYPD detective, is dumped by his girlfriend Samantha for being emotionally shut off. John's childhood friend Gordo (Noah Emmerich) finds a Heathkit#The SB-series and HW-series Single-sideband modulation ham radio that once belonged to Frank, but fails to get it working. The night before the anniversary of his father's death, John is surprised to find the radio broadcasting during an occurrence of the aurora borealis, and has a brief conversation with another man concerning the 1969 World Series, which John is able to recount in specific detail. Eventually, he realizes that the other man is his father in 1969 and tries to warn him of his impending death. The next day, while attempting to rescue a young girl, Frank remembers John's warning and manages to escape the warehouse. That evening, the two reconnect and learn a great deal about each other's lives.