The Big Bang Theory will say goodbye to actress Carol Ann Susi  and to her unseen character, Mrs. Wolowitz on February 19th.

Getty Images; Frederick M. Brown

TVLine reports the storyline is tied to Stuart re-opening his bookstore, and in it is furniture from Mrs. Wolowitz' home. The other story line in the episode features actor Nathan Fillion from Castle.

Susi died from cancer back in November.