Stuart Bloom (Kevin Sussman) may have killed Howard's (Simon Helberg) mom, Mrs. Debbie Wolowitz (voiced by Carol Ann Susi) in , at least according to one hypothesis. It's been more than two years since the CBS sitcom wrapped up after 12 seasons. However, thanks to reruns, not to mention its availability on various streaming services around the world. Given this, viewers have been revisiting the show and picking up information that may have slipped them the first time they watched it.
Premiering in 2007, The Big Bang Theory revolved around a group of geniuses who were also dubbed as social outcasts.
In The Big Bang Theory season 7 finale, it's revealed that the comic book shop owner moved into the Wolowitzes after his business suffered a fire.
To further back this theory up, the source added that when Howard's mother left for her last trip, Stuart took the liberty of taking the furniture from her den. He claimed that Debbie allowed her to take them, but it's a big coincidence that Howard could no longer confirm this with his mom because she died thereafter. Assuming that Stuart did plan out Mrs. Wolowitz's demise, the timing of the re-opening of the comic book store was also perfect. That meant that he no longer needed to keep her as leverage against Howard, who was getting increasingly suspicious that he was mooching off of his mother.
Admittedly, it's a pretty dark idea for a sitcom like The Big Bang Theory - but also one that does have some credibility behind it. The timing of events line up, and Stuart has the motivation to do the crime. At this point, there's no way to know if this can be accepted as canon. Nevertheless, it's an interesting notion to ponder on.