As well as allowing viewers to catch up with the pair and their ghostly housemates, the season's premiere featured a moving tribute in honour of a crew member who had passed away at the end of the episode.
A dedication appeared just prior to the credits reading: "In loving memory of our friend Kevin Corbishley."
Kevin had worked as a light rigger on since season 2, but tragically died towards the beginning of filming on the latest run of episodes.
The news came as a terrible shock to the cast and crew of Ghosts, which has remained largely unchanged since the acclaimed series began, with many strong friendships being forged across the team in that time.
Kevin also worked as a rigger on BBC One medical drama Call the Midwife and received a tribute at the end of the season 11 finale, which first aired in February of this year.
The message read: "In memory of Kev Corbishley: 1965 - 2022."
In response to the dedication, a fan asked the production about Kevin's role via Twitter, and the official Call the Midwife account responded.
"A dearly loved member of our crew who died very recently. He will be missed," the reply said.
The tweet received more than a thousand likes as well as dozens of replies from viewers sending their well wishes and expressing their gratitude for Kevin's work on a show that means so much to so many.
Ghosts season 4 continues the story of homeowners Alison and Mike, who inherit a dilapidated manor house inhabited by an eccentric group of spirits from various time periods.