The second season of Marvel’s “Agents of SHIELD” will add at least four new characters to the series, including a new villain, the company announced Friday at Comic-Con in San Diego.

Lucy Lawless has been confirmed to play Isabelle Hartley, a tough longtime SHIELD veteran who is good with a knife.

British newcomer Nick Blood will play mercenary Lance Hunter, who will assist the SHIELD agents. The character is best known for being the director of S.T.R.I.K.E., a British intelligence agency that worked with Captain America and Captain Britain to defeat Red Skull.

The newest villain to the show, Daniel Whitehall, will be played by Reed Diamond. The character is a member of Hydra and known by his alias the Kraken, who when wearing his signature helmet, is covered in body armor. In the comicbooks, he spends decades training Hydra agents at a school for orphaned girls to become human weapons.

SHIELD agent Barbara Morse, also known as Mockingbird, will be the next significant comicbook hero to join the series. The character, who gets her name for taunting her opponents in battle, has close ties to Clint Barton (Hawkeye) and the Avengers in the books. No actress was announced.

And Patton Oswalt will return to the series, in which he guest starred as Agent Koenig, only this time, he plays twins, Sam and Billy.

The series started shooting its newest episodes on July 24.