Is it a fool-proof method using polygraphs, microexpressions watchers and truth serum combined to detect liars?

A practiced, talented sociopath might be able to pass those tests.

50 years ago I was told how to falsify a lie-detector. Has to do with stuffing something into your shoe to make it uncomfortable, bordering on pain. Take you time while answering all questions.

^I was told that you can falsify polygraph readings, by having a thumb tack in your shoe. To my knowledge, polygraphs, are not a trusted source of truth. For example. If a person is really stressed out, they may “fail” many truthful answers. Even, the base questions.

There are many variables.

A lie detector cannot detect a lie when the subject believes what they say at the moment.

Truth serum would induce a mental state which would render the polygraph useless.

Polygraph tests are not admissible in court. That should tell you everything you need to know.