I think todays precap is really misleading... why would Yash hire a detective to follow Aarti... there is not enough doubt yet.. he trusts Aarti blindly.
I think the precap definetly relates to Paridhi and her lie.. somehow these two lies are going to interwine.. now that Paridhi has seen Aarti...she is going to be more inclined to watch Aarti closer!!!