'Pretty Little Liars' season 7 spoilers, plot news: Big surprises await the Liars

"Pretty Little Liars" season 7 continues to be as intriguing as when it premiered in June. In the next episode entitled, "Along Comes Mary," a liar receives a proposal, two snoops make a surprising discovery, hostilities give rise to a confrontation between two long-time enemies, and the biggest of all surprises, a dead ringer for someone they buried haunts the liars.

The promotional video for episode 5 of "Pretty Little Liars" season 7 made some titillating revelations that are bound to have fans caught up in the excitement of waiting for next week's serving of the show.

The hostilities between Jenna (Tammin Sursok) and Alison (Sasha Pieterse) give rise to a confrontation between them, and the audience is given a hint that the former may be on to what the liars have done to Elliot (Huw Collins).

As Jenna leaves the scene in front of Alison's home, the latter cries out and asks the former to pass on a message to Archer. Jenna replies with a comment hinting that she might know what has happened to Archer.

Speaking of Archer, in the meantime, the two snoops, Emily (Shay Mitchell) and Aria (Lucy Hale), discover Elliot's true identity. In the previous episode, Jenna alluded to the guy as Archer, and the trailer video shows the two liars finding the name, Archer Dunhill, on a book and make the connection. Alison's husband Elliot, who had been torturing her at the institution, is Archer Dunhill.

The plot thickens as more questions pile up after these events are shown in the teaser. Who is Archer Dunhill, and how does Jenna come to know him?

The mystery does not end there because another revelation comes up in the video. Archer or Elliot has been located. Marco (Nicolas Gonzalez) informs Alison her husband had been sighted in Baltimore. He is apparently alive and well.

In another development, Caleb (Tyler Jordon Blackburn) is missing and cannot be found. As for Alison, with Mary Drake (Andrea Parker) keeping close tabs on her, she finds it hard to get away.

On the lighter side, a proposal is teased for the next episode. Is it of the wedding bells kind, or something ominous? But who could be getting married?

All these will be shed light on when "Pretty Little Liars" season 7 returns with episode 5 on Freeform on Tuesday, July 19.