Abe

In a child's bedroom, 1978, a comatose, amphibious man was found inside a water-filled capsule within a long-lost chamber beneath the St. Trinian's Hospital. Found by a group of plumbers, the Bureau for Paranormal Research and Defense quickly intercepted the creature, and nicknamed it “Abraham Sapien,” in reference to the scrap of paper written on his tube: April 14th 1865 - the date of President Abraham Lincoln's assassination.

Unresponsive for weeks, it wasn't until B.P.R.D. scientists experimented with shocking him did he awake. However, it appears that Abe was at least somewhat aware of what was going on, as he has memories of overhearing one of the scientists debating whether or not to give up trying to revive him and just skip to dissection. Abe is an extremely talented swimmer, with a natural affinity for water. He can breathe both air and water, but can only stay out of water for about a week; when travelling, he sleeps in hotel bathtubs to keep his skin from drying out. He is sensitive to the condition of water he swims in. When swimming in Venice, the water was so polluted that he had to stay in his tank for a long time afterwards to recover.

He is a talented marksman, as well as one of the most skilled agents in the B.P.R.D. (beside Hellboy and Liz), with decades of experience.

He also appears to have greatly enhanced strength and healing capabilities. Some (but by no means all) of the wounds he has survived include being speared in the chest (so severely he was initially declared dead), getting shot multiple times and then tortured by an ape, being thrown onto large spikes, and being shot in the face and chest (again, declared dead for some time). Whether or not his body even can die is up for debate, as both times he's been declared dead he's returned to life.

It's also possible that he does not age, or that he ages at a much slower rate than normal humans, given that he was in the tube under the hospital for 113 years while he made his transformation. This may be a trait he inherited from his previous life as Langdon Everett Caul, who was roughly seventy at the time he became Abe, while still looking quite young.

It is possible he has some limited psychometry, although the instances of psychometry may actually be properties of the object he's interacting with, not an ability he possesses.

Abe Sapien possesses unique psychic abilities, and requires a water-breathing device when out of the water for long periods of time. He is portrayed as having a rather passive personality, and has a sibling-like relationship with the more direct, “beat stuff into submission, ask questions later” philosophy of Hellboy. As well as having a fondness for thousand-year eggs.

Abe's more comedic side is touched on. The fact that he does not remember his past life means he is completely inexperienced with love and relationships, and finds himself at a loss of how to act around Nuala. However, he finally tells her how he felt as she dies in his arms at the end of the film, through telepathy.

In the B.P.R.D, he lives in a tank for of water and on the other side of the glass is a library where he can read as he pleases. The tank is very simple with nothing really decorating it.