Saugeen Shores Police Criminal Investigations and Drug Branch arrested one man last Thursday then went to a home the next day Friday and executed a search warrant there.
Four more people were arrested at the scene, three were released from custody without charges.
A 36-year-old man from Port Elgin was held for a bail hearing.
A 25-year-old woman of no fixed address was released with a future court date.
Drugs seized include fentanyl and other opioids, and methamphetamine.