How did Red come to know Mr. Kaplan?

In this photo, we see Mr. Kaplan putting on her cleaner gloves for the very first time.

The Blacklistreturns with a two-hour episode on Thursday, April 20 at 9 p.m.

The Blacklist - Season 4

Credit: Virginia Sherwood/NBC

The Blacklist - Season 4

Virginia Sherwood/NBC

The Blacklist - Season 4

Virginia Sherwood/NBC