Citigroup Inc. made a banking blunder of colossal proportions, depositing $81 trillion into a client’s account—instead of the… $280 they were actually owed. The staggering “miscalculation” lasted only a few hours before the bank swiftly reversed the transaction. However, the incident, which seemed straight out of a sci-fi movie, did not go unnoticed, as revealed by the Financial Times.

The transfer slipped past two employees and was finally caught by a third employee 90 minutes after it was processed, according to the report. No funds actually left the bank, and the event was classified as a “near miss” in reports to the Federal Reserve and the Office of the Comptroller of the Currency.

“Even though a payment of this magnitude could never have actually been executed, our monitoring controls immediately detected the input error between two internal Citi ledger accounts, and we reversed the entry,” a Citigroup spokesperson said in an email response. “Our preventive controls would also have blocked any funds from leaving the bank.”

The incident had no impact on the bank or its client, the spokesperson added.

A total of 10 near-miss incidents involving $1 billion or more occurred at Citi last year, according to the FT, citing an internal report. Although this marks a decrease from 13 cases the previous year, the report noted that near misses exceeding $1 billion were considered rare across the entire U.S. banking sector.