Meryl’s the primary female character in the Solid Snake-led games in the Metal Gear Solid series, the first game and the fourth (Solid Snake appears in 2, but mainly as a supporting character to Raiden; and he isn’t even born/created yet in 3). She’s the daughter of Roy Campbell, although she initially believes Roy to be her uncle; in fact, Roy had an affair with Meryl’s mother, who was married to Roy’s brother, who died in the Gulf War.
Funny thing about Meryl, is that although she was created by Hideo Kojima, the character first appears in the sci-fi, Lethal Weapon-inspired adventure game, Policenauts. Although similar in appearance, personality and name, the Meryl in this game is pretty much a completely different character in the continuity of Metal Gear. Unless she decided to do some moonlighting as a police officer on a space colony between the first and fourth games.
Meryl had joined FOXHOUND-the special forces team formed by Big Boss, and having among it’s members Solid Snake-recently when the unit rebelled at Shadow Moses island. Not wanting to participate in the rebellion, she was jailed, but managed to steal a guard’s (Johnny Sasaki, the man who she would later marry!) uniform and disguise herself. After some initial distrust-due in part due to Solid Snake resembling his twin brother, the revolt’s leader Liquid, and her relative inexperience compared to him. However, the two eventually learn trust and respect, and she began to help him on their mission. She also shows a sort of rebellious attitude, wanting to be taken seriously as a female soldier by Snake and her “uncle”.
At one point, when fighting the strange Psycho Mantis, Meryl becomes briefly mind controlled by him, and she nearly not only almost kills Snake but herself.
After recovering, she unfortunately is badly wounded by another FOXHOUND member, Sniper Wolf. This is where the game takes too turns. Later on there’s a torture sequence, where if Snake resists, Meryl will live; but if he gives in, she’ll die. This actually gives you one or two endings depending on the outcome.
The “bad” ending has Snake take Otacon with him to escape the facility, after Snake mourns her death. The “good” ending has both survive, and Meryl escape the facility with her instead (Although Otacon gets out the other way).
As they drive into the sunrise, Snake and Meryl seem to be falling in love a bit, with Snake starting to realize her beauty, and considering giving up the soldier’s life.
That of course, doesn’t last long, as Snake once again goes into the field as part of Philanthropy, working to take down Metal Gear knock-offs, and later getting involved in the Big Shell Incident. He also ages rapidly due to his clone nature which doesn’t help either. Meryl also learns the truth about her father. Also, the ‘good’ ending is obviously the one in continuity, as Meryl reemerged in Metal Gear Solid IV, leading her own group, the Rat Patrol 01 (an anagram, interestingly enough, of Patriots). The group also features Johnny, the guard who she stole the guard clothes from. It’s revealed he’s got a serious crush on her, although he’s a bit clumsy and has very bad stomach problems.
Meryl’s original Metal Gear Solid IV design. This was later tweaked a bit into the lower version, giving her more muscle and a more realistic face.
Despite their competency and skill and combat (although they are unknowingly being used as pawns by the Patriots AIs), Meryl-aiding Solid Snake in his guest to take out Liquid Ocelot-are outsmarted by Ocelot, who takes control of the Patriot’s SOP (Son of the Patriots) system, which controls the world’s soldiers (Except for Johnny, who has none, so he’s out of sync with the rest of Rat Patrol)-first by messing with the Patriots-controlled Nanomachines in her bloodstream, causing them to seize, and secondly, by shutting down their weapons with the same system later on.
It’s during this incident that she nearly drowns, but Johnny is able to save her by performing CPR. She then kisses him.
Later on, Meryl becomes part of the group to take down Ocelot’s OUTER HAVEN ship, along with Johnny and Snake. After briefly being controlled by Ocelot’s henchwoman Screaming Mantis (sort of a reincarnated Psycho Mantis), Meryl-joined by Johnny-then face off against the Dwarf Gekkos and FROG unit soldiers to buy Snake more time.
They also propose to each other during the battle, both accepting.
After the battle, Meryl settles things with her father, having him walk her down the Aisle. She then marries Johnny, giving at least these two characters a really happy ending, in a series which has a lot of bad, or tragic ones for many of the characters.