  We present deep observations of CO(3-2) from the Cloverleaf lensed
quasar-starburst at $z=2.56$. We discover a 4-5 times less massive companion at
a projected distance of 33 kpc from the Cloverleaf host galaxy. The galaxies
are connected by a bridge of CO emission, indicating that they are interacting
and that the companion is being stripped by the Cloverleaf. We also find
evidence for fast molecular gas in the spectral line of the Cloverleaf that may
be an outflow induced by stellar or quasar feedback. All of these features may
be ubiquitous among quasars and only detected here with the help of
gravitational lensing and the sensitivity of the data. Overall, these findings
agree with galaxy formation scenarios that predict gas-rich mergers play a key
role in quasar triggering, starburst triggering and the formation of compact
spheroids.
