We finally know when Timeless will come to an end (again). The twice canceled, twice revived NBC series' two-part series finale will air Thursday, Dec. 20 at 8/7c, NBC announced Friday.

The two-hour event will pick up shortly after the Season 2 cliffhanger and find Wyatt (Matt Lanter) and Lucy (Abigail Spencer) traveling across three centuries and two continents in an attempt to reverse Rufus' (Malcolm Barrett) death. The episodes will also take full advantage of the festive broadcast date, with the series finale including "a healthy dose of Christmas spirit," per NBC. So if we don't see Abigail Spencer and Matt Lanter wearing adorable Christmas hats the Clockblockers may have to send another helicopter message in protest.

In addition to the return of Spencer, Lanter and Barrett, Goran Višnjić, Paterson Joseph, Sakina Jaffrey and Claudia Doumit will also reprise their roles for the final series finale.

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The episodes will mark Timeless third time saying goodbye. It was briefly canceled after its first season before NBC renewed it for a second season. It was then canceled again after Season 2, but the network ultimately listened to the fan outcry once more and renewed it for the special two-hour event, allowing creators Eric Kripke and Shawn Ryan to provide a real ending for fans.

So, Clockblockers, are you ready to say goodbye for real on Thursday, Dec. 20? Yeah, us neither.