Whare can u watch previous and current episodes on the web?

Well CBS plays the 4 most recent aired episode that played on TV at : link
(Just go down to full episodes)

As for as old episodes I'm not sure about those, youtube used to have a few but most got removed due to copyright issues. I'm sure some of the other have links to some but if I coem across some sites I'll try to link them.

Or if you have no access in the cbs vids you can try this one:
link

You can watch them on youtube or the cbs website. You can even go on xfinity on demand, click tv series, and i think click catch up.

The BEST website to watch episodes is sidereel.com and watchseries.eu is also an amazing website. I have watched so many episodes of many tv shows, and these websites are no-doubt the best!