Allison Janney Takes the Lead as Mom Returns for Season 8

Chuck Lorre's mother/daughter comedy Mom loses its daughter tonight as it kicks off its eight season on CBS with Allison Janey as its central character after her costar Anna Faris exited the show for unknown reasons over the summmer

Also today: Clare Crawley blows up The Bachelorette, Superstore bids farewell to America Ferrera, and Maisie Williams is back with a vengeance in a new dark comedy on HBO Max. Here's what's new and noteworthy on TV this busy Thursday:

SEASON PREMIERE: Bonnie (Allison Janney) invites the ladies over for a slumber party on the season premiere of Mom, but it isn't long before a night of fun and childhood games exposes some very grownup problems. 9:00 PM ET on CBS

MILESTONE EPISODE: NBC marks a bittersweet milestone tonight, as Superstore airs its 100th episode, and America Ferrera makes her long-delayed exit. Watch the preview. 8:00 PM ET on NBC

NEW EPISODE: To the surprise of no one, it appears The Bachelorette rumors are true. Tonight, Clare Crawley blows up the show before Tayshia Adams steps in to take her place. 8:00 PM ET on ABC

SERIES PREMIERE: Silicon Valley's Thomas Middleditch returns to series TV in Chuck Lorre's latest CBS comedy, B Positive. When divorced father Drew (Middleditch) learns he needs a kidney transplant, a chance meeting with his old friend Gina (Annaleigh Ashford) leads her to offer him one of hers.. Watch the trailer. 8:30 PM ET on CBS

SEASON PREMIERE: Eleven year-old Sheldon Cooper (Iain Armitage) graduates from high school as Young Sheldon returns for its fourth season, but turns out he's not as ready for college as he expected to be. Watch the trailer. 8:00 PM ET on CBS

DOCUSERIES PREMIERE: The four-part Netflix original docuseries Carmel: Who Killed María Marta? looks at the unexplained death of socialite Maria Marta García Belsunce, who was originally thought to have fallen and hit her head in the bathtub before an autopsy proved otherwise. Streaming on Netflix

SERIES PREMIERE: Maisie Williams stars as a 20-something oddball who sets off on a coming of age adventure in search of her dad's killer in the six episode British dark comedy Two Weeks to Live. Sian Clifford (Fleabag) plays her doomsday-prepping mother. Watch the trailer. Streaming on HBO Max

Mike Attebery is Senior Editor at Primetimer and the author of seven mystery thrillers. Follow him on Twitter at @mikeattebery.