Freeze! William Atherton is coming on board an episode of Castle.

The veteran actor (Ghostbusters, Die Hard, The Practice, Desperate Housewives) will appear on an October episode of the ABC series as a "life-extension researcher," according to the network, named Dr. Ari Weiss. An expert in cryogenic freezing, Castle and Beckett will seek his help when they come across a murder scene...

... with no body.

Of course, the show's main guest star next season will be Penny Johnson Jerald as Victoria Gates. Read what this actress has to say about this key role NOW.