From an old episode of Stargate SG-1:
Col. O’Neill: It’s time for Plan B.
Maj. Carter: We have a Plan B?
Col. O’Neill: No, but it’s time for one.
Today the Russians have grounded their entire fleet of Soyuz spacecraft after one of them was destroyed in a crash. This is, of course, the vehicle that NASA is relying on to resupply the ISS since the last shuttle has retired. Currently, there is no backup. The crew of the ISS is stranded in orbit until either the Russians fix the problems with the Soyuz or SpaceX begins commercial flights to orbit.
As I’ve said before, the replacement for the shuttle should have been in service 20 years ago.