TNT orders Season 4 of 'Snowpiercer'

July 30 (UPI) -- TNT has ordered a fourth season of its post-apocalypstic train drama, Snowpiercer.

The cable network said Thursday it recently wrapped production on Season 3, which stars Daveed Diggs, Jennifer Connelly, Rowen Blanchard, Mike O'Malley, Alison Wright and Sean Bean.

The new episodes, featuring new cast members Archie Panjabi and Chelsea Harris, are expected to air early next year.

"Snowpiercer has been an incredibly successful series for us that continues to capture the imagination of viewers, grow audience and maintain strong ratings," Sam Linsky and Adrienne O'Riain -- co-heads of scripted original programming for TBS, TNT and truTV -- said in a joint statement.

"All of our seasons embark on an emotional, unexpected ride and the well-plotted storylines will continue to evolve and remain relevant to audiences. We're excited to keep the train running into Season 4."

The show is about the passengers aboard a train that perpetually circles a globe that was frozen over during a catastrophic event that wiped out most of the life on the planet.