If you have cable, then TNT. There isn't really anywhere that you can watch it for free. But, if you have an Amazon Prime subscription, it's on Prime Video.
Episodes89. Top-rated. Tue, Mar 22, 1966. S1.E10; Return of the Killer: Part 1. Dr. Tracy, Jack, and Mike leave the compound to look for a wounded leopard, not.
EPISODE 1. I Haven't Told You Everything · EPISODE 2. To Keep Us Safe · EPISODE 3. Protect Them from the Truth · EPISODE 4. A Matter of Life and Death.