The "Sons of Anarchy" and "Vikings" star returned to the long-running procedural Wednesday in a new leadership position and will appear in the rest of season 15.

[WARNING: Spoilers ahead for Wednesday's episode of Law & Order: SVU, "Beast's Obsession"]

Law & Order: SVU welcomed back a familiar face.

Donal Logue, who guest-starred in a March episode of the veteran NBC procedural, made a splashy return as Lieutenant Declan Murphy in Wednesday's pivotal hour, "Beast's Obsession," taking over from Olivia Benson (Mariska Hargitay) as acting commander of the New York Special Victims Unit. The episode culminated in a confrontation between Olivia and "The Beast," William Lewis (Pablo Schreiber), who committed suicide.

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With this episode, Logue has been promoted to recurring status for the rest of SVU's 15th season, The Hollywood Reporter has learned.

Logue assuming the top post marks the latest change on SVU this season. Dann Florek's exit as Captain Cragen in episode 11 was the catalyst for Benson's temporary stint as boss, and Richard Belzer, who had played John Munch since Homicide: Life on the Street began in 1993, departed in episode five.

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Logue's continuing SVU gig marks a busy few weeks for the Sons of Anarchy and Vikings star, whose past TV credits include Terriers, Copper, Life and Grounded for Life. He next appears as Detective Harvey Bullock in Fox's straight-to-series Batman prequel Gotham, starring Ben McKenzie as a young Jim Gordon. He is repped by UTA and Kipperman Management.

SVU, which is awaiting a renewal from NBC, goes off the air for several weeks; it returns April 30 with new episodes, starting with "Post-Mortem Blues." According to the official synopsis, the SVU is forced to deal with the aftermath of Lewis' suicide when the IAB investigation into Benson's actions comes up inconclusive. Her nightmare continues as a lengthy trial and insufficient evidence put her career in jeopardy.

Law & Order: SVU airs Wednesdays at 9 p.m. on NBC.

Email: Philiana.Ng@THR.com

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