The fright wig is instantly recognisable. Even with her back turned, it’s obviously Tina Turner on stage. Except it isn’t. It’s actress Emi Wokoma playing the singer in a performance virtually guaranteed to turn her into a star. Casualty and EastEnders will soon be distant memories for Wokoma. Good for her, maybe, but she’s the best thing about the otherwise wafer-thin Soul Sister.

Since 2004, the Ambassador Group’s Trafalgar Studios has done sterling work in staging West End transfers for some of London’s most promising fringe talents. Kieran Lynn’s An Incident at the Border arrives in the centre of town from the Finborough Theatre, where it was seen in July. It has a good cast and, because of its sceptical attitude to the pervading aesthetics of naturalism in contemporary playwriting, lots of promise. But can it live up to expectations?

I, Tommy, Gilded Balloon ****

Everybody will be familiar with Tommy Sheridan's story, and not necessarily because they closely follow Scottish politics at their most internecine. Rather because the Glaswegian socialist went from being barely a paragraph in broadsheets to being plastered over the front pages of tabloids after a series of revelations – which he strongly denies – about visiting swingers' clubs.

Tam o' Shanter, Assembly Hall ****

Scottish schoolchildren are brought up on Robert Burns but other British students aren't so fortunate. We may know snatches of the great man's work – “Wee, sleekit, cow'rin, tim'rous beastie”, “O, my Luve's like a red, red rose” and so on – but few of us could recite even a stanza of Tam o' Shanter.

Jigsy, Assembly Rooms ****

Les Dennis may have started his career as a comic, and then as a presenter of cheesy, family-friendly television game shows, but of late he has been plying his trade as a very decent actor. And so it proves again in Tony Staveacre's one-man play about a washed up Liverpudlian club comic.

The ever-libidinous Guy (Jason Durr) is "as subtle as a fire engine" when it comes to sex, or so we're told during the course of Volcano, and it's difficult not to feel that this belated Noël Coward discovery could be similarly described in theatrical terms. Never performed during Sir Noël's life, the 1956 play will constitute essential viewing for completists of the Master who want a further sense of how this protean talent's singular career evolved.

Mies Julie, Assembly Hall ****

Miss Julie is pretty full-on at the best of times but in Yael Farber’s striking new version, Strindberg’s themes of class and gender are given a shocking modern makeover. In transposing the action to present-day South Africa, she has written a story about the divide that still exists between the haves and have-nots, and the crippling emotional history that has yet to be overcome by the young nation.

It’s brave to take Shakespeare into the West End in midsummer – and in this of all summers. Greg Doran’s all-black, African Caesar certainly doesn’t lack for impact, colour, zest, urgency. It takes the audience by the scruff of the neck and rams the play down our throats. The concept is impressive. The set, half Roman amphitheatre, half Nazi bunker dominated by a giant effigy, its back towards us with arm raised in totemic salute, summons up TV images of dictators who eventually come crashing down, from Stalin to Mubarak and who knows how many more to come.

Is it the greatest story ever told, or the most indulgent nativity ever staged? The return of the York Mystery Plays – this summer’s blue-ribbon theatrical spectacular in the North – begins by beguiling, ends up bemusing, while in between is a sacred story about the eternal battle of good and evil, from Creation to the Last Judgement. The show’s subject matter is as epic as its telling, which involves more than 1700 volunteers (including 500 cast members) and takes place in the ruins of St Mary’s Abbey. It is the UK’s largest outdoor theatre production this year.

Rosie Wilby: How (Not) to Make it in Britpop, Bongo Club ***

In the 1990s Rosie Wilby was lurking on the outer edges of Britpop with her band Wilby, whose giddy career highlights included opening for Tony Hadley (he evacuated the entire room for the soundcheck), being clamped outside the venue while supporting Bob Geldof, and getting their own plastic name tag in the racks of Virgin Megastore.