The 'Leftovers' actress joins Rob Lowe in '911: Lone Star,' which is set to debut at midseason.

Fox's 911 spinoff has found its female lead in Liv Tyler.

The Leftovers and Lord of the Rings actress will star with Rob Lowe in 911: Lone Star, which received a straight-to-series order from the network in May. The role will be Tyler's first on a broadcast series.

The spinoff, from 911 creators Ryan Murphy, Brad Falchuk and Tim Minear, stars Lowe as a New York City firefighter who moves with his son to Austin, where he tries to balance saving people who are at their most vulnerable and solving problems in his own life.

Tyler will play Michelle Blake, a chief paramedic who's a little rock 'n' roll and sometimes a bad girl, but always the boss. Brilliant and wry, she matches wits with Lowe's Owen in the station but is also obsessed with finding out what happened to her younger sister, who disappeared two years earlier.

The series is set to premiere Jan. 19, 2020, following the NFC Championship game on Fox, then move to Mondays while parent show 911 takes a midseason break.

Murphy, Falchuk and showrunner Minear executive produce, and Lowe is a co-executive producer of the 20th Century Fox-produced show.

Tyler's recent credits include Hulu's Harlots and the BBC miniseries Gunpowder. She also stars with Brad Pitt in the feature Ad Astra, set for release Sept. 20. Tyler is repped by UTA and Untitled Entertainment.

Deadline first reported the news.