As previously reported, Daniel Evans' revival opens on 16 December (previews from 29 November) and runs until 25 January 2014.
Richards, whose TV credits include Footballers' Wives and The Bill, will star opposite Phil Davis, recently seen in the BBC's Sherlock, as Fagin.
Richards' stage credits include the WhatsOnStage Award-winning West End production of Priscilla, Queen of the Desert.
Also in the cast are Samual Bailey (age 12) and Jack Skilbeck Dunn (age 11), who share the title role of Oliver Twist, and Jack Armstrong (age 13) and Travis Caddy (age 14) alternating as the Artful Dodger. All four boys were selected from open auditions held at Sheffield Theatres.
Oliver! is Evans' third musical for Sheffield Theatres, after last year's My Fair Lady and Tim Firth's This Is My Family.
Based on the novel by Charles Dickens, Oliver! is the story of an orphan who runs away from a workhouse and falls in with a gang of boys trained to be pickpockets by gang leader, Fagin.
The score includes "Food Glorious Food", "I'd Do Anything", "As Long As He Needs Me", "You've Got to Pick a Pocket or Two" and "Oom-Pah-Pah".
Also announced today is the full company for Paul Miller's production of The Winter's Tale, which precedes Oliver! in the Crucible (from 2 October – 2 November).
The cast will feature the previously announced Daniel Lapaine, alongside Suzanne Ahmet, Will Alexander, Keir Charles, Christian Dixon, Eva Feiler, Jonathan Firth, Sam Graham, Jake Harders, Barbara Marten, David Mallinson, Andy McKeane, Kirsty Oswald, Claire Price, Patrick Walshe McBride and Gareth Williams.