Simon Helberg as Howard Wolowitz – Then
Though often looked down upon by Sheldon because he ‘only’ holds a Master’s degree in engineering from MIT, Howard eventually manages to parlay his expertise into becoming an astronaut for NASA. In the early seasons, Howard was often trying and failing to score a date with a variety of different women, That all changed with Penny introduces him to her coworker Bernadette in season 3, who was working at the Cheesecake Factory in order to pay for grad school.
Simon Helberg as Howard Wolowitz – Now
Simon is another one of the original cast who has been with The Big Bang Theory since day one, when he was introduced as the nerdy mama’s boy, still caught under his overbearing mother’s thumb. Recently, Simon has also managed to fit in several film appearances in addition to his work on The Big Bang Theory, including a turn as the pianist Cosme McMoon in Florence Foster Jenkins, which also starred Meryl Streep and Hugh Grant.
Laura Spencer as Emily Sweeney – Then
Laura Spencer plays the slightly morbid dermatologist that Raj meets via online dating during the seventh season of the show. She becomes entangled in a love triangle with Raj and another woman he’s dating, Lucy, but Emily is unfazed. The two enjoy watching horror movies together, and she entertains Raj with macabre jokes. They eventually enter into a fairly serious relationship, but Raj finds in the end that he is still struggling with commitment.
Laura Spencer as Emily Sweeney – Now
Raj wasn’t the only one two timing, as Laura Spencer was also appearing in Bones as Jessica Warren, which recently wrapped production. While it’s unclear whether or not Laura will reprise her role as Emily in the near future, as Raj recently broke up with her again, she doesn’t seem to have ruled out the possibility. In the meantime, Laura recently filmed a short film called Vitality, where she plays the role of Christine.
Kevin Sussman as Stuart Bloom – Then
Kevin Sussman was introduced to the show as Stuart during the second season, as the owner of comic book store that the guys frequent in Pasadena. Though he isn’t one of the core members of the group, Stuart often pops up during their misadventures, though the character struggles even more than they do to fit in. Stuart is characterized by his often depressed demeanor that is usually the result of some mishap or another.
