Marcus and Sydney locate an old colleague Mokhtar who is their local liaison in episode 1x04 “A Broken Heart”.
Source: IMDb
Marcus and Mokhtar watch from overhead while Sydney blends in with the crowd to listen in on Luc Jacqnoud's meeting in episode 1x04 “A Broken Heart”.
The kids walk down into a secret chamber beneath Alex's house and discover their parents performing some sort of strange ritual with Destiny in episode 1x01 “Reunion”. The kids manage to escape the temple before their parents see them and earlier their parents prepare for the sacrifice in episode 1x02 “Rewind”. The kids enter the temple look to rescue Andre but discover it empty. They then search for clues and discover a hidden camera in episode 1x05 “Kingdom”.
Years before, Jonah shows Geoffrey and Catherine the temple and the PRIDE members perform their first sacrifice.
Alex recovers footage showing the very first sacrifice.
Source: MCU Location Scout
Source: IMDb