I listened to this podcast a few weeks ago and found it really well done.
Kudos to Tablet for consistently producing really interesting content.
Mikvah is an ancient Jewish practice and it is the foundation of Jewish family life.
The concept is Family Purity, or in Hebrew "Taharat Hamishpacha" in case you would like to learn more about it.
New Jewish communities must build a mikvah before building a synagogue, it's that important.
The podcast is less than a half hour and it's a very good introduction to the concept for those who do not know about it, and also has some very engaging and intellectually satisfying commentary for those who practice mikvah.