In what appears to be their most mature series to date, Andrea Brillantes and Seth Fedelin took their fans on a roller-coaster of emotions as streaming service iQiyi released on Tuesday the official trailer of “Saying Goodbye.”

Shown during the media conference for the much-awaited series, the trailer opens on a light note with Elise (Brillantes) and Ricky (Fedelin) crossing paths at a music store, fighting over a CD of Yeng Constantino.

This meeting signals the start of the friendship between Elise and Ricky, who even start a fans club of Constantino in Pampanga.

But the sweet scenes turn into a shocking twist as Ricky collapses in a meeting with fellow Yengsters. It turns out he has a heart disease.

Yet despite Ricky’s condition, Elisse, who is a medical student, has already fallen in love with him.

The trailer leaves an important question to the viewers: “Pag puso na ang nakataya, goodbye na ba o laban pa?”

“Saying Goodbye” is one of four Filipino original romantic series from the partnership of iQiyi and ABS-CBN announced Tuesday.

Brillantes and Fedelin’s new project will start streaming on iQiyi on December 4 at 8 p.m. Former "PBB" housemates Andy Abaya and Kobie Brown are also part of the cast.

• 'Hello Heart,' 'Saying Goodbye' to premiere via iQiyi in December

The love team, also known as SethDrea, has starred in “Kadenang Ginto” and “Huwag Kang Mangamba.”