Trish almost drowning...
- In Episode 4, a drunk Trish falls into the swimming pool and almost drowns when the pool cover begins to close. It's only when her brother-in-law Richard dives in to pull her out at the last minute that she can be saved. Henry shows up almost immediately afterward, and Richard explains that it's a good thing he was there, or 'this could have been bad'. The event is mentioned once in a throw-away line at the start of the next episode but, like so many other things in the first half of the show, is forgotten Post-Headspade, as the characters presumably have other things to worry about.
- This becomes more interesting, however, if you remember events that had transpired earlier in that episode. Trish accidentally got a glimpse of Richard and Katherine having some fun together, and told Henry what she'd seen, in tears. At the bachelor party, Henry confronted Richard about this, implying that he would tell Thomas, but Richard doesn't seem to believe him. Why? Richard is well aware that Thomas hates him, and probably wouldn't doubt any accusation coming from his beloved daughter. Richard is confident Henry and Trish won't tell Thomas because he'll make sure they have a good reason to stay quiet. The pool cover didn't close automatically: Richard activated it, just so he could save Trish, putting them in his debt, and preserving his secret.
The shower turned on in Malcolm's room...
- Another Big-Lipped Alligator Moment from the earlier episodes is in Episode 5, when Malcolm wakes up from a tormented nightmare over Booth's death. He notices the shower has been left running, and briefly wonders if it's Booth, probably hoping it to be true. There's nobody there of course, and the water was presumably running all night. One could conclude Malcolm just turned on the shower when he got back the previous night and, in his shell-shocked state, forgot to take a shower, just going to sleep. There is another possibility, though: when Danny appears in the bathroom doorway, startling Malcolm, he mentions the door to the bedroom was open. While Malcolm could just have forgotten to lock the door for the same reason he forgot to take a shower, it may be that somebody broke in.
- Henry confessed to Sully in Episode 13 that he only placed Marty's bag of money on Hunter's boat just to see what kind of trouble could be stirred up among his friends. It may even be that Henry and Wakefield had some prearranged deal to kill whoever drew the short straw, and had to bury the money. Wakefield could very well have been waiting in the woods to kill Booth, when Malcolm turned up and inadvertently did the job for him. When Malcolm goes to The Cannery for the bachelor party, Henry asks where Booth is, and Malcolm clumsily says he doesn't know, and hasn't seen him. Henry, who is very good at lying, may have noticed Malcolm's evasion, coupled with his lateness to the party and desperate need for cash, and concluded that Malcolm may have killed Booth to get his hands on the money. Henry may have decided to torture Malcolm more because of this as only he can kill his friends, and he believes his motives are more just than Malcolm's greed. So he broke into Malcolm's room that night (maybe with a stolen or duplicate master key) and turned on the shower, just to torture him, see how long he could go before cracking. Henry had little to lose at that point...Mr. Wellington was supposed to die that afternoon, kicking the whole plan in motion, and why not give Sheriff Mills an extra Red Herring murder to slow him down?
Why certain people died when they did.
- Marty was killed on the first night because he, alone of everyone else on the island, knew that Henry had been adopted. Since he was the younger brother of Frank Dunn, it seems unlikely something as big as his brother and sister-in-law adopting a son could slip by his notice, even for somebody notoriously living it up. He was probably kept to secrecy by Frank and Karen, and it's debatable whether or not he knew about Wakefield and Sarah's status as Henry's biological parents. Either way, it became pertinent to get rid of Marty as early as possible, to keep him from getting suspicious as the situation worsened. Bonus points, as Wakefield got to kill him, thereby personally doing in another 'unsatisfactory' father figure for his son.
- Lucy was killed, presumably because she already had plans to leave the island the next day. Henry didn't want to leave any loose ends, so every member of the bridal party had to die. When he learned that Lucy was supposed to leave before the wedding, he and Wakefield seized on the chance to get rid of somebody whose absence would cause no immediate concern.
- Hunter was more of a personal problem for Henry, who saw Hunter as a genuine asshole who had mistreated Trish, and was willing to whore himself out for the sake of breaking up the wedding. Even though Henry had no intention of actual marrying Trish, he still took it upon himself to break into his motel room and set up that trap for Trish to meet 'Hunter'. Killing him as he was leaving, just to get rid of him for good, was probably more for personal gratification than anything else. Also, a convenient excuse to place Marty's bag of money for the groomsmen to find the next day.
- Thomas was one of the few deaths (others possibly being Marty and Charlie) whose exact time and manner would have been determined from the start. Henry and Wakefield needed a large spectacle to draw everybody's attention and officially cancel the wedding festivities, setting things in motion for the rest of their plan. Henry's dislike of Mr. Wellington is clear enough, and Henry had probably taken it upon himself to kill all the Wellingtons personally as, unlike his family and friends, they were only a part of this party because he was using Trish. Henry may have felt it a twisted kind of justice to get rid of them himself.
- Richard needed to die so Wakefield could use his 'disappearance' as leverage for Madison to play along when she was kidnapped, implicating Charlie as a prime suspect. Henry probably had no scruples about killing Richard either, given his apparent genuine contempt over Richard and Katherine's affair, and Richard's attitude toward it. Besides, Henry had more to benefit out of J.D. being the central suspect, than Richard.
- Malcolm was killed as he was burning the money. Henry had by now perhaps inferred Malcolm was responsible for Booth's death (see above WMG), and thereby determined to give him a more brutal death than otherwise. Whereas Henry still had some affection for Sully and Danny, his feelings for Malcolm would have been largely those of contempt and, with the money destroyed, Malcolm was no longer of any use to Henry.
- It is suggested a few times (and is a widely held Fanon theory, to boot) that Henry never intended J.D. to die. In earlier episodes, he tried to get J.D to return to the mainland before things got bad. Because of J.D's unfortunate Roman candle prank that was supposed to occur during the wedding rehearsal, however, J.D becomes a prime suspect in Thomas's death. Henry then decides to do all he can to get J.D arrested, simply so he can sit in a jail cell and wait out the rest of the murders, maybe to live out the rest of his days in Henry's idyllic paradise, as much a captive as Abby. He wasn't counting on Wakefield shooting Deputy Garret so that J.D could have easy access to the keys, thereby freeing himself. When Henry went down to the docks to keep Sully, Beth, Cal and Chloe from stealing a boat and escaping, he encountered J.D first and forced himself to do what he needed to do, resulting in the struggle that got him those scratches on his arms.
- Beth's murder was likely one of convenience. Wakefield needed somebody to go missing into the tunnels, so that the wedding party would be forced to search them, finding Madison so that she could spread around her story of Charlie being the one who kidnapped her. Sully and Danny leave Beth behind in the kitchen when they hear Henry and Shane arguing, making Beth easy pickings for Wakefield, who would have been lying in wait at the tunnel entrance.
- Katherine's murder is problematic, largely because there is really no time frame in which Henry could have sneaked into the solarium and stabbed her, all without being noticed by Shane. She may have been targeted for being more isolated than the other remaining members of the party, and Henry would have wanted to leave out that one loose end, wedding out the last Wellington whose death Trish wouldn't exactly get teary over, to spare her as much grief as he could.
- Maggie only died because she left the relative safety of the Cannery, that much is established fact. It's unclear when Henry and Wakefield had initially planned to kill her off, but it may have been during the Cannery blood bath, as the older woman would be an easy target.
- Charlie, of course, was Wakefield's big revenge. An elaborate death trap where Charlie could be made to suffer, trapped and waiting for death, forced to have one final confrontation with his daughter, because Wakefield revealed himself to her.
- Nikki and Shane were both killed at the Cannery because they were the only ones who actively moved to fight back. Nikki ran for the shotgun she kept under the bar, so Wakefield moved to her first, overpowering her before she could get off a shot. Shane, of course, stayed behind to give the other girls a chance to get away.
- Wakefield kidnapped Chloe, presumably because she reminded him of Sarah, perhaps by being flirtatious (it's suggested Sarah used to hop from guy to guy and 'easy', despite her cleverness. Wakefield may have been somewhat impressed by Cal's dedication to her, which inspired him to test Cal and Chloe For the Evulz. Cal presumably passed the test, and died for it, whereas Chloe refused to let Wakefield kill her.
- Danny is pretty straightforward, as Wakefield probably pegged the young, physically trim man as the biggest threat alongside a nine-year-old girl and her sleeping mother. Wakefield went to him first, and Danny fought him off long enough for Shea and Madison to escape.
- Trish's death seemed to be a joint effort on Henry and Wakefield's part. Wakefield makes a noise outside the bungalow, Henry goes to investigate, Wakefield breaks the door down, cornering Trish, though he allowed her to escape through a window. Trish runs into Henry's waiting arms, he confesses, and then kills her.