River Song's Diary is a rare Artifact — Book card from Doctor Who (WHO), collector number 1051. Current market price: — (foil $4.49), TCGplayer market prices via Scryfall.
Imprint — Whenever a player casts an instant or sorcery spell from their hand, exile it instead of putting it into a graveyard as it resolves. At the beginning of your upkeep, if there are four or more cards exiled with this artifact, choose one of them at random. You may cast it without paying its mana cost.