LTCM is a hedge fund founded by the bond arbitrage group from Salomon, plus Nobel laureate economists (Merton and Scholes) from Harvard.
They operated from 1994 to 1998, culminating in $1 turning into over $4 for each dollar invested in 1993 (and a $4.5 billion total capital), and losing it all (each $1 worth 33 cents) in 5 weeks in 1998. The Fed organized a bailout operation to ingest capital to LTCM from major Wall Street banks, out of fear of LTCM collapsing triggering a series of crises.