This week's number one star Mika makes a sure-to-be-messy appearance at the Popstarz, The Fleadh Tour 2007 moves indoors and Biffy Clyro top the Kerrang! Tour bill...

Mika
The Scala, N1
This week's number one star celebrates the triumph of his single Grace Kelly, not with a large-scale concert but with a sure-to-be-messy appearance at the Popstarz club night. Now that the Beirut-born singer has proved there's a huge audience for his glittery glam pop, this could be the last chance to see the whites of his eyes. (020 7833 2022). Tonight, 10pm-4am.

The Fleadh Tour 2007
Wembley Arena
Once a one-day festival of music with a vaguely Irish connection in Finsbury Park, this year the Fleadh shrinks somewhat and moves indoors. While country music tops the bill in the hairy shape of Texan hippy Willie Nelson, fans of Irish folk will find succour in the Sharon Shannon Big Band and Damien Dempsey. Fleadh regular Eddi Reader completes the line-up. (0870 060 0870). Tonight, 6.30pm.

Bonnie "Prince" Billy
Queen Elizabeth Hall, SE1
Enigmatic singer-songwriter Will Oldham is a tough artist to grasp, preferring to hide behind numerous aliases, rapidly changing musical styles and a big beard, but his latest work as Billy, The Letting Go, contains some of his most delicately affecting ghost folk to date. (08703 800 400). Tonight, Sat 27 Jan, 7pm.

Kerrang! Tour
Astoria, WC2
While the NME is taking over most of London with their branded gigs in February, their rock weekly rivals have settled for one tour featuring their favourite new bands. The bill is headed by Biffy Clyro, cult favourites for some time who look imminently chartward bound. Warming up the headbangers will be The Bronx, theAudition and I Am Ghost. (020 8963 0940). Sat 27 Jan, 6pm.

Pussycat Dolls & Rihanna
Wembley Arena
Wembley becomes Glamourpuss Central again, as two of the planet's most popular, least clothed pop acts return to the venue to perform their numerous hits. A Pussycat Dolls show in Kuala Lumpur this summer was fined for gross indecency, so expect much writhing. (0870 060 0870). Sun 28 Jan, 6.30pm.