Officer West is in for a big surprise when he and Bradford go on patrol in this week’s episode of ABC’s The Rookie.

In the episode “The Switch,” airing Tuesday at 10/9c, the rookies are temporarily paired with new training officers. For example, Nolan (played by Nathan Fillion) is paired with Lopez (Alyssa Diaz) in the pursuit of an escaped criminal, while West (Titus Makin Jr.) is forced to face his fears after being partnered with Bradford (Eric Winter).

Part of the lesson West will be taught is about to be touched on in the sneak peek above, as he is introduced to Wallace Barry, an eccentric shut-in with a caustic sense of humor and hidden compassion. Filling the guest-starring role of Wallace is — casting spoiler alert! — Irish actor Kristian Nairn, whom Game of Thrones fans know as Hodor. Press play above to see their introduction plays out.

Elsewhere in Tuesday’s episode, officers Chen (Melissa O’Neill) and Nolan must face a hard truth.

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