Answered: Help. 60s/70s Stylish movie about Superbug.

I caught this movie for free on YouTube last year.

There's a massive lab in the desert somewhere in America (probably Nevada), which is making superbugs, and bombs that can unleash them.

At the start, someone comes in and craftily steals the bug, by impersonating the scientist. He kills the real scientist and leaves his body in the lab, and exits the area by pretending to be him. The lab is guarded by a giant circular lock door - the ones that guard the bank safes.

The hero, a spy, is called in. He first checks whether there's a leak, by entering the lab in a suit and holding a lab rat.

Later, he along with the heroine track down the two criminals. One of the actors playing the criminals passed away recently.

There is a fight in the helicopter at the climax, where the hero grabs back the device holding the superbug, after pushing the Villian out of the helicopter.

The movie was stylishly shot. Especially the lighting was excellent.

Thanks in advance.