The half-hour special, set during the time period of the drama's companion series, "Fear the Walking Dead", chronicles a group of passengers facing a walker attack while in flight, reported Entertainment Weekly.
One character who survives that encounter will then join the cast of "Fear the Walking Dead" on season two.
The airline attack story will debut online, and will unfold in chapters that will air during "Walking Dead"s on-air telecasts.
The special episode will be produced by Dave Erickson and "Fear" co-executive producer David Weiner.
"The Walking Dead" will return on October 11.