With only three episodes left of The Big Bang Theory, teases for the show’s finale have begun to emerge - including the reveal that there will be a surprise cameo in the one-hour special. Could that unexpected guest be Howard’s (Simon Helberg) father?

Much has been said about Howard’s close (sometimes too close) relationship with his mom, Debbie Wolowitz aka. Mrs. Wolowitz (Carol Ann Susi).  She had been a constant figure in The Big Bang Theory, although we never really get to see her. That said, the vivid descriptions from her son gave us a pretty good idea about what she looks like. Her presence was only established through her voice, more often than not while communicating with Howard, screaming. Debbie died in season 8’s “The Comic Book Store Regeneration,” and in her passing the mystery of her husband deepened after the Wolowitz patriarch signed off their family home to Howard without contacting his son.

There’s very little known about Howard’s father, Sam Holowitz, but that doesn’t mean that he’s not an integral part of his son’s arc. He’s been mentioned a handful of episodes throughout The Big Bang Theory’s 12-year run with the first one dating back all the way to season 3’s “The Precious Fragmentation.” It’s been established that Sam abandoned his first family when Howard is 11, but the reason remains unknown. Back in “The Closet Reconfiguration,” Howard could have almost found out more about his dad after Sheldon (Jim Parsons) discovered a letter sent to him on his eighteenth birthday by his dad - but he refused to read it and ended up burning it up instead.

To help him cope with this lingering mystery, the gang (who all knew what was in the letter after Sheldon blabbed about it) came up with different stories about what the letter said… But its real content has never been revealed. The emergence of Josh (Matt Bennett), Howard’s supposed half-brother who’s an oceanography student from San Diego, revealed that Sam moved on with a second family, although it’s unclear if he’s still with them or he left them too.

While Sam’s whereabouts have never been a central mystery in The Big Bang Theory following Josh’s appearance, Howard’s traumatic experience with his father played a role as he entered fatherhood - particularly when he and Bernadette (Melissa Rauch) had Michael. Fortunately, he was able to overcome it (oddly, thanks to a pep talk from Sheldon). But with this particular subplot still having no resolution, it makes sense that surprise visitor in the show’s finale is a well-known actor playing Howard’s dad.

At this point, The Big Bang Theory has already brought in most of its dream guest stars. Mark Hamill and William Shatner both made their cameos recently, and throughout the years, we’ve seen Bill Gates, James Earl Jones, Elon Musk, Neil deGrasse Tyson and Stan Lee among others reinforcing the gang’s love for all things geeky. So if the show brings another big name from any of the same world, there’s really no novelty to that. However, if they tap an A-list play Howard’s father and reveal him in the finale, not only they’re able to have another Hollywood star in the show, his appearance also services the show’s narrative.

The final season of The Big Bang Theory has barely referred back to anything that’s built up in its last 12 years, and frankly, that’s a missed opportunity considering that there’s a lot of things to pull from. Sure, there are a couple of references and a few familiar faces that have returned, but for the most part, they’re focused on the things that have been established more recently. Bringing Howard’s dad to cap off his story would be a great way to wrap up one of the most heartfelt storylines in the show which sadly didn’t get the proper attention it deserves.

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