Into the Story
Instant
This spell costs 
less to cast if an opponent has seven or more cards in their graveyard.
Draw four cards.
The boundary between real and imaginary is as thin as the page, and just as easily torn.
Jason Rainville
Throne of Eldraine (ELD)
• #50Rulings
Into the Story's cost reduction can only reduce its cost by {3}. It doesn't reduce the cost further if more than one opponent has seven cards in their graveyard or if an opponent has fourteen cards in their graveyard.
(wotc • 2019-10-04)
To determine the total cost of a spell, start with the mana cost or alternative cost you're paying, add any cost increases, then apply any cost reductions (such as that of Into the Story). The mana value of the spell remains unchanged, no matter what the total cost to cast it was.
(wotc • 2019-10-04)
Rulings
Into the Story's cost reduction can only reduce its cost by {3}. It doesn't reduce the cost further if more than one opponent has seven cards in their graveyard or if an opponent has fourteen cards in their graveyard.
(wotc • 2019-10-04)
To determine the total cost of a spell, start with the mana cost or alternative cost you're paying, add any cost increases, then apply any cost reductions (such as that of Into the Story). The mana value of the spell remains unchanged, no matter what the total cost to cast it was.
(wotc • 2019-10-04)