Mild spoilers if you did not watch last Sunday's Line of Duty (episode 4)

Vicky McClure’s Line of Duty character DS Kate Fleming has been a fixture on the hit police corruption drama for four series – but for how much longer?

Last week we saw Kate’s traditional undercover role exposed by Thandie Newton’s wily adversary Roz Huntley – and McClure has revealed that if Fleming does survive to the end of series four there will have to be some changes to her story for the next run.

“You can only be undercover so often, so if I am in series five there will have to be some changes,” she tells tonight’s edition of The Graham Norton Show.

Asked if her character makes it to the end of the current series, she said: "You are always waiting for the writer to kill you off". But she added: “I am definitely in next week’s episode.” 

McClure obviously refused to reveal how the series would end but promised that this Sunday’s episode – and the finale the following week – will be gripping.

“So much happens in the last two hours. It is great.” 

McClure appears on The Graham Norton Show alongside Rob Brydon, Brendan O’Carroll and Harry Styles.

The Graham Norton Show is on BBC1 tonight at 10:35pm