Family Guy: Sir Ian McKellen Cast as Stewie's [Spoiler] in Season 15

Stewie Griffin is making an appointment with Sir Ian McKellen.

The Academy Award-nominated actor, who most recently starred on the ITV comedy Vicious, is set to guest-star in an upcoming episode of Family Guy, EW.com reports.

McKellen will lend his voice to the character of Dr. Pritchfield, a child psychologist appointed to Stewie after the youngest member of the Griffin family acts up in school. Whether or not Pritchfield is able to make progress with Stewie is anyone’s guess, but they’ll surely have plenty to discuss — not limited to his well-known desire to kill Lois and take over the world.

The episode, penned by Vicious scribe Gary Janetti, is set to air in Spring 2018. Meanwhile, Family Guy kicks off its 15th season on Sunday, Oct. 1 at 9/8c on Fox.