NEW YORK - It is, one could argue, the single most important piece of the giant transportation puzzle that blankets New York City.
Without the subway system, how would millions of people get around, get to work, and get home?
Hard to imagine.
And how did we get to this point, where so many things seem to be going wrong.. and how do we get out of it?
Joining us this week is MTA Chairman Joe Lhota.
Up Close: MTA Chairman Joe Lhota
Also this week, are we about to go head to head with North Korea, including perhaps militarily?
And why would President Trump be sending messages to the special counsel who has now convened a grand jury to look into the Trump campaign?
With us are political analyst Hank Sheinkopf and ABC News political director Rick Klein, who joins us from our Washington bureau.
Up Close: North Korea