when (one's) ship comes in
When one becomes wealthy and/or successful. When my ship comes in, I'm moving out of this disgusting little apartment first thing!
when one's ship comes in
When one has made one's fortune, as in When my ship comes in I'll get a Mercedes or better. This term alludes to ships returning from far-off places with a cargo of valuables. It may be obsolescent. [Mid-1800s]