The Big Bang Theory season 9

Production

The show had already been locked in for three more years back in March 2014, covering seasons eight, nine, and ten through the 2016–17 TV season. Like the year before, the first six episodes of season nine landed on a different night because CBS had snagged Thursday Night Football. At their upfront presentation in May 2015, the network announced the season would kick off on Mondays and then slide back to Thursdays once football wrapped up. Cast members Melissa Rauch and Kunal Nayyar tweeted that filming began on August 5, 2015.

Laurie Metcalf came back as Sheldon’s mother Mary for episodes one and twenty-four, while Keith Carradine returned as Penny’s dad Wyatt in episode three. Sheldon’s maternal grandmother, Constance—whom he calls “Meemaw”—finally showed up in episode fourteen, played by June Squibb. Leonard’s father Alfred also made his first appearance in episode twenty-four, portrayed by Judd Hirsch. This season marked the first time every main cast member appeared, including former regular Sara Gilbert, who guest-starred in the 200th episode.

Reception

The ninth season drew a mixed response, especially regarding its first episode. John Doyle from The Globe and Mail found the 200th episode, "The Celebration Experimentation," unfunny, calling its jokes repetitive, outdated, and stale. Tom Eames of Digital Spy felt Leonard and Penny's relationship lacked the passionate tension of a classic will-they-won't-they romance, and that their marriage felt like an anticlimactic letdown. In contrast, Ashley Bissette Sumerel of TV Fanatic thought the season premiere, "The Matrimonial Momentum," was enjoyable despite its serious tone.