CBS will continue the Big Bang Theory’s amazing streak of cameos this year, adding Nathan Fillion to the ranks later this month. The popular star of ‘Castle,’ and former star of such epic franchises as ‘Firefly’ and ‘Buffy The Vampire Slayer,’ will be playing himself in an upcoming role. That episode is scheduled to appear on February 19, 2015.

In the episode both Raj (played by Kunal Nayyar) and Leonard (played by Johnny Galecki) see Fillion at a local restaurant, but aren’t sure if it’s actually him or not. The duo then have to work up the nerve to speak to the actor. It’s a similar episode to when the full-crew (minus Penny and the other girls) saw Summer Glau (also a star of Firefly) on a train.

All four of the male roles on the show have expressed their love for ‘Firefly’ and ‘Buffy’ in the past, it was only a matter of time before the star appeared on the popular show. Other notable additions that have come on the show include Brent Spiner (Data from Star Trek), Steve Wozniak, George Takei, Bob Newhart, Stan Lee and Stephen Hawking.

The show has continued to be a remarkable success for CBS, currently in its eight season. For the last three seasons the show has seen an average of 18 million viewers, making it easily one of the most popular series, not only on CBS, but on television today. The show stars Johnny Galecki, Jim Parsons, Kaley Cuoco-Sweeting, Simon Helberg, Kunal Nayyar, Mayim Bialik and Melissa Rauch.