Kath, a shy young woman, befriends Bob, the reclusive gardener at a seaside hotel where she's getting married. Kath has never come to terms with her mother leaving home when she was eight and that her overbearing father, Ken, never talks about her. Now she is getting married to escape, only to discover that her fiancée, Steve, is completely dominated by Ken as well. Bob is a gentle, eccentric man with a dry sense of humour and a troubled past. He spent a long time in prison and in the years he's worked at the hotel he has never ventured beyond the gardens, which he tends with obsessive care. Kath sparks a connection to an unresolved relationship from Bob's past with a girl called Louise which resonates so strongly that he feels compelled to leave the safety of the hotel and confront his past.
Tras la ruptura de un acuerdo milenario entre la humanidad y los poderes invisibles de un mundo fantástico, el infierno en la Tierra está cada vez más cerca. Un líder despiadado, que se maneja tanto en el mundo de los humanos como en el de las criaturas, decide traicionar a sus ancestros, y despierta a un ejército imparable de criaturas diabólicas. Ahora, en este momento de debilidad, el superhéroe más duro deberá combatir contra el imparable líder y su ejército. Es rojo, caliente e incomprendido es Hellboy (Ron Perlman).
