Adam Charles

Adam Charles aka "Toast" is a computer hacker and occasional ally to the Hawaii Five-0 Task Force.

Toast is a computer hacker who appears in Ohana. He was assisted at an earlier point by Detective Danny Williams, whom he has given the nickname of "Jersey".

His epithet of Toast comes from the fact that when he isn't working on computers, he's smoking marijuana. This nickname was given to him by Det. Danny Williams. It is later explained in S6E22 ("I'ike Ke Ao") that his nickname also comes from the fact that his love for breakfast toast is unparalleled and that it helped give birth to his nickname.

Season 1
In the first season, he appears on the second episode ("Ohana") where detective Williams asks for his help in decrypting some information on a kidnapping victim's personal computer, and realize how powerful a 'skeleton key' can be and what the implications of its usage can be.
 * Ohana

Season 3
Toast appears again in S3E07 ("Ohuna"). He has gotten a job as an IT guy at Digi-Dome to support his roommates, identified only by their hacker names ("Rocky" and "Bullwinkle").
 * Ohuna

Toast's family is apparently Jewish, as his roommate says he has left for Baltimore, Maryland to attend his sister's Bat Mitzvah.

Season 4
Toast analyses the footage from the destroyed tablet table and the team discover that during and after the siege the NLM found Adam and Kono's location in Zhejiang, China and sold it to the Yakuza, prompting Chin to call Kono and warn her while also stating that she and Adam should leave right away.
 * Aloha ke kani I ke kani

Season 6
In S6E22 ("I'ike Ke Ao"), Toast, now a millionaire from creating an "addictive" mobile phone game, appears yet again where he lends a hand to the Five 0 task-force in order to help locate and save a kidnapped female college student from a dangerous vigilante.
 * I'ike Ke Ao

Season 8
In S8E04 (E uhi wale no 'a'ole e nalo, he imu puhi), Toast is found, deceased, from multiple gunshot wounds and lacerations.
 * No Matter How Much One Covers a Steaming Imu, The Smoke Will Rise

Abilities

 * Hacking
 * Computer Programming