Award-winning funnyman Alan Carr concludes the fourth series of what's become one of the UK's favourite entertainment shows - now that Wossy's off the air. Alan's hospitality (i.e. plying all guests with Lambrini) and infectious personality have cemented him as the perfect chat show host, inviting his guests to let their hair down, have a good old natter and most importantly, have fun. In this final episode of the current run, pop star and Russell Brand's fiancée, Katy Perry, chats to Alan and performs her latest single Teenage Dream. Big Brother host Davina McCall stops by to talk about 10 years of Big Brother, ahead of this year's big finale, and chat show host Paul O'Grady tells Alan about the recently published second part of his autobiography The Devil Rides Out, as well as reviving Lily Savage for panto, and his new chat show. Plus, Killers front man Brandon Flowers gives an exclusive performance of his debut solo single Crossfire . Plugarama.