She said that the promise of "achhe din" will work against the Modi government in the same manner as 'India Shining' campaign did against the Vajpayee government in 2004.
She alleged that freedom of the people was "under systematic and sustained assault" and there was a long-in-the-making project to refashion the very idea of India.
Delivering the keynote address at the India Today Conclave 2018 in Mumbai, the former Congress President said all this was being done by attempts to rewrite history, "falsifying facts and slandering nation builders and fanning prejudice and bigotry".
Answering a question about the possibility of the BJP and the NDA coming back to power in 2019, Mrs Gandhi shot back: "No we are going to come back. We are not going to let them come back."
To another query about bitterly-opposed parties coming together to take on the BJP which is seen as a colossus and unbeatable singly by anyone, she said "it is a difficult task. If all of us think of the larger picture, if we really think and care for the country, then we should sink local differences which really deal with state politics".
On her dinner invitation to opposition leaders next week, she said: "We try to have regular meetings with like-minded parties to see if we can work together. We have worked together in the past. In Parliament, specially in the Rajya Sabha, there is a certain amount of coordination. Yes, I do that."
In her speech, Mrs Gandhi said that provocative statements from the ruling establishment were neither random nor accidental but "part of a dangerous design".
"Fear and intimidation are the order of the day. Alternative voices are being silenced - literally, in far too many cases, through violence, even murder. The freedom to think for oneself, to differ and disagree, to eat according to one's choice, to meet or marry according to one's wishes - all this and more - is under attack," she said.
"Today we are being presented with an alternative and indeed regressive vision of who we were as a people, what we are and what we should be. This re-imagination is based on a distorted perception of our history and it is a fatally flawed view of what will secure our future."
She referred to frequent disruptions in Parliament and said it worked much better during the first NDA government led by Atal Bihari Vajpayee.
Mrs Gandhi said the Congress may have a President outside of the Nehru-Gandhi family in the future.
She accused the BJP of wrongly creating an impression that the Congress was a "Muslim party" and said public attention to temple visits of party chief Rahul Gandhi was aimed at countering that perception.
The former Congress chief talked of her role in bringing like-minded opposition parties together against the ruling BJP and said while it was easy to do so at national level, the parties face a lot of pressure from their local units.
In her speech, Mrs Gandhi made unrelenting attacks on the Modi government which has completed almost four years in office.
"Our society, our freedom, all are now under systematic and sustained assault. Make no mistake about it. This is a well thought out project long in the making to refashion the very idea of India," Mrs Gandhi said, adding "Vigilante mobs and private armies have been let loose with state patronage."
She said callous remarks were being made about changing the Constitution that "point to a deliberate attempt to subvert the very essence of India".
The Congress leader said religious tensions were being fuelled and there was shocking insensitivity to atrocities on Dalits and women.
"Our society is being polarised with an eye to winning election"," she said.
"Our very social DNA is being re-engineered. The resulting churn will unleash pent up frustration, resentment and anger, with devastating consequences. Individuals can mesmerise for a while but our Republic needs impartial and robust institutions."
"Was India really a giant black hole" before the BJP-led government came to power in 2014, she asked. "Did India's march to progress, prosperity and greatness begin only four years ago? Is this claim not an insult to the intelligence of our people?"
She said parliamentary majority was being interpreted as a license to stifle debate and bulldoze legislation.
"Political opponents are being targeted through the misuse of investigative agencies. The judiciary is in turmoil. Civil society is being silenced. Universities and students are being strait-jacketed. Much of the media is being coerced away from its proper watchdog role - which is surely to expose mis-governance, scams and frauds."
Noting that the noise of politics is the music of democracy, she said these were being muffled.
"The pretext is to make India a 10-trillion dollar economy. Yes, of course, we need to move fast but fast - F, A, S, T -- cannot stand for First Act, Second Think."
Asking if maximum governance means "minimum truth", she said "all of a sudden we are told that seven and a half million jobs were created in 2017.
"This claim has, of course, been widely debunked, but does that make a difference? No, it doesn't, because as soon as one myth is demolished, another takes its place," she said.
Mrs Gandhi, who stepped back as party chief in December, said people need to see things as they are and not be taken in by skillful repackaging and lavish marketing.