EastEnders has a surprise lined up for viewers in tonight's episode, which show bosses are encouraging to watch as it's broadcast on BBC1 at 7.30pm.
"We can't believe we've kept it under wraps," a show insider told RadioTimes.com this morning. "Everyone's keeping tight-lipped, but it's definitely one to see live."
The comment comes after executive producer Dominic Treadwell-Collins wrote on Twitter that EastEnders fans wouldn't want to miss tonight's instalment.
The soap's official website has also been teasing followers, promising that this evening's episode would be one to watch.
And the EastEnders press account has got in on the act this morning too, telling people to cancel all plans for 7.30pm:
EastEnders has held back many secrets this year prior to transmission. The return of Jane Beale, the reveal of Shirley being Mick's mum, plus Jay and Ben's cover-up of their actions on the night Lucy was murdered have all created shocks for viewers.
"This is just the start of the treats we have in store for the autumn," our source added.
Current EastEnders storylines see Phil Mitchell preparing to marry Sharon Rickman and Kat Moon trying to cope with the injuries she sustained in a recent house fire. But viewers will have to wait until tonight's episode airs to see what fresh shocks the scriptwriters have in store.