Here are the top 10 points in this big story:
The Income Tax Department on Wednesday began searches at the homes and offices of Ms Pannu and Mr Kashyap and his partners who launched the now-defunct production house Phantom Films.
The searches, part of a tax evasion probe against Phantom Films and carried out across 28 locations in Mumbai and Pune, also covered Reliance Entertainment group CEO Shibhasish Sarkar and some executives of celebrity and talent management companies KWAN and Exceed.
WhatsApp chat logs, emails, documents and computer peripherals were seized from various locations. Ms Pannu, 33, and Mr Kashyap, 48, who were shooting in Pune, have been questioned by the tax officers.
The others searched include some employees of Phantom, which was dissolved in 2018, and its other promoters director-producer Vikramaditya Motwane, producer Vikas Bahl and producer-distributor Madhu Mantena.
"During the search, evidence of huge suppression of income by the leading film production house compared to the actual box office collections has been unearthed. The company officials have not been able to explain discrepancy of around Rs. 300 crore," the Income Tax Department said in a news release.
"Evidence related to manipulation and under-valuation of share transactions of the production house amongst the film directors and shareholders, having tax implication of about Rs 350 crore has been found and is being further investigated," it said.
"Evidence of cash receipts by the leading actress amounting to Rs 5 crore has been recovered. Further investigation is going on," the department said, without naming Ms Pannu.
"Apart from this, non-genuine/bogus expenditure to related concerns by the leading producers/director having tax implication of about Rs 20 crore has been detected. Similar findings have been made in the case of the leading actress also," it added.
Both Anurag Kashyap and Taapsee Pannu are outspoken critics of the government and have lent their voice to various causes, including the ongoing farmer protests and last year's protests against the controversial citizenship law that challenged PM Modi.
A string of opposition leaders have criticised the raids since Wednesday. Congress leader Rahul Gandhi used three popular Hindi idioms on Thursday to hit out at the government and the hashtag "ModiRaidsProFarmers".
Watch: Anurag Kashyap Fixes Daughter Aaliyah's Veil During Her Registry Taapsee Pannu Begins Filming For Gandhari. See Viral Pics Anurag Kashyap Shares Pics From Daughter Aaliyah Kashyap's Wedding: "Ye Bhi Gayi" Video: Rahul Gandhi Approaches BJP MP Who Fell During Protest, This Happens People Seeking Justice For Atul Subhash Chase Rahul Gandhi. He Does This Congress VS BJP Showdown Over Amit Shah's Remark On BR Ambedkar Top Court Extends Stay On Defamation Case Proceedings Against Arvind Kejriwal "BJP's Bid To Distract From Ambedkar Row": Rahul Gandhi On Parliament Tussle Probe Launched As "Blast" Takes Place Outside Police Chowki In Punjab Track Latest News Live on NDTV.com and get news updates from India and around the world.