No endings or suffixes are added to verbs in Russian for English Past Perfect case. Gramatically there is only one Past Tense in Russian.
We say "I met here 10 years ago" but "I had met her before I went to study" in English, but in Russian the verb doesn't change its form in these examples:
"Я познакомился с ней 10 лет назад", "Я познакомился с ней до того, как пошел учиться".