From CBS: “Harper’s Island” is about a group of family and friends who travel to a secluded island off the coast of Seattle for a destination wedding. This island is famous for a streak of unsolved murders from seven years ago. Although they’ve come to laugh and to love, what they don’t know is they’ve also come … to die.

We kick off with Sheriff Mills finding daughter Abby sleeping on ex Jimmy’s couch — an awkward but largely innocuous situation barring the fact that Jimmy is vamping about in a towel. The sheriff and Jimmy apparently bonded after Abby fled to L.A. seven years following her mother’s murder, and they had breakfast plans, and Abby’s asked to join. Excellent. She can rebond with both before they’re either killed or labeled a suspect. Seems about right for episode five.

Another unlikely bond? That would be groom Henry’s brother, J.D., and maid-of-honor Shea Allen’s daughter, Miranda, over some illicit fireworks. Mad scientist Miranda thinks she could help J.D. set them off and upset the wedding planning team, which is what happens. They make sort of existential, we’re-both-social-outcasts, aren’t-we-type comments, which is plausible for preadolescent, mad scientist Miranda but not so much J.D. I know people with tattoos, J.D. The ink didn’t cause any brain damage.

Trish is pacing around all bride-to-be-like and has abandoned the pearls for the seriousness of the occasion. Groom-to-be Henry suggests she might benefit from taking the morning off and sends her away for a bike ride with her dad, Thomas Wellington. Henry is then whisked away to a discussion with the inn manager about white versus ecru napkin rings, which can’t help his homicidal tendencies, I think.

Trish and Dad take their bike ride and slow down when they spot the show’s true star, the frou-frou dog Gigi, running loose in the woods since her owner’s disappearance. Gigi emotes hunger and chill in the wilderness like nobody’s business. This is a convenient point for Trish to explain that Gigi’s owner, Lucy, a bridesmaid, had “left” the island (she was burned to death in a pit), with apparently no curiousity about her departure. Still not adding up, CBS. Anyway, Trish and Dad follow Gigi and walk into another woodland booby trap that involves a rig setting off a log that soars down from above and hits Trish and Dad’s bicycles, because the timing and physics involved are much easier than using a shotgun to kill them, of course. They survive, which we expected because they’re in previews for a yet-unseen church rehearsal, and the subsequent attack by the trap-setter’s German shepherd is also relatively uneventful. What is eventful: Thomas tells his daughter he doesn’t trust Henry (gold star for you, Tom; I suspect him, too), and when she in turn reveals Dad’s new wife, Katherine, is carrying on with son-in-law Richard Allen, Tom looks crushed and uses “cuckold” in a sentence, which is not a word you pull out very often outside of an 18th-century British drama class. You’re growing on me, Tom. That can’t be good for you.

Henry is sent in search of the still-missing pastor, killed in episode two, and finds a raccoon head on the church vestibule. He looks genuinely alarmed, so maybe this isn’t his doing but perhaps another “Deliverance”-esque prank by brother J.D. Still, it’s a chance for him to look up Sheriff Mills, who in the course of cleaning up the mess suggests he is grateful that Henry’s wedding allowed him to reconnect with Abby. Henry intimates that Abby blames the sheriff for some of her issues and also that his parents died mysteriously — usually another red flag for vengeful serial killers. But we don’t learn the reason the Dunns lost their parents.

In a parallel shot, Abby has stopped by Dad’s place to happily reminisce over old photos, but she goes too far when she visits the attic. (Casual visitors, even relatives, should not pop into an attic, I think.) She finds Sheriff Mills has covered it in newspaper clippings and other potential evidence that his wife’s murderer was, perhaps, not the real killer. I don’t care, because if it weren’t for newspapers, how could we have helpful props in crime stories? OK. That’s my plug for our print edition. Had to be said. Some clippings suggest unsolved murders in nearby Washington state locales looked like a “Wakefield copycat.”

Henry goes a-sleuthin’ to see whether J.D. left the raccoon at the church. He charms Miranda into admitting she has seen J.D. and the firecrackers but, more importantly, that she has a lot of “friends” on the island. This should either be alarming that she’s befriended a killer or that a local is protecting her from Henry. That’s my guess. Henry goes on to rough up J.D. and say he knows he’s responsible for the animal deaths, and J.D. suggests he has another surprise in store. The easy solution would be that J.D. is nuts. The more subtle option is that J.D. is the good guy who knows Henry’s a homicidal madman, and I prefer that theory. But props to CBS, they’re holding their deck of cards close. Neither are for sure implicated.

And then, wow. This show gets so good. Cut to church rehearsal. Trish and Dad walk down the aisle toward the innkeeper, who is running the show in the pastor’s absence. Henry emotes love to Trish and crazy to any other viewers tuning in. Sully is a humble best man escorting deluded Shea down the aisle, she who does not realize husband Richard is carrying on with her stepmother. Poor Tom does know the score, though, and somehow manages to not strangle Richard or Katherine. Abby rehearses her role as a reader. Then CBS starts cutting back/forth to the sheriff’s hunt and discovery — body part by body part — of the pastor. He tries to call Abby, who shuts off her phone. And wow. Tom and granddaughter Miranda are at the pew now in the rehearsal, and a sharp-looking chandelier falls down amid Miranda’s screams. See you, Tom. Once you pulled out “cuckold,” you lost an audience. Anyone on a major network program has to stick with amateur-hour vocabulary.