Cronos

Jesus Gris

Angel de la Guardia

De la Guardia

Mercedes

Aurora

Tito

Alchemist

Manuelito

Funeral Director

Narrator (voice)

Buyer

Bleeding Man

Drunk

Stoned Man

Tango Student

Tango Student

Tango Student

Tango Student

Tango Student

Tango Student

Mimo (as Francisco Sánchez)

Watchman

The alchemist at the beginning of the movie is named Fulcanelli, which was the pseudonym of a famous french alchemist of the late 19th/early 20th century, who mysteriously disappeared in the 1940s and whose real name and identity has never been known.

Mechanical objects and special effects were carried out by Guillermo del Toro's own monster and make up FX company "Necropia" (The company no longer exists, but was functional for 15 years).

Guillermo del Toro:  [clockwork]  Various shots from inside the Cronos Device.

When Jesús searches for Aurora after she has taken the Cronos, as he walks through two doors, he stops. Behind him, reflected in the glass of the door, is crew and equipment.

Jesus Gris: I am Jesus... Gris... Jesus Gris... Jesus Gris.

Aurora Gris: Grandfather.

Narrator: [over the opening sequence] In 1536, fleeing from the Inquisition, the alchemist Uberto Fulcanelli disembarked in Veracruz, Mexico. Appointed official watchmaker to the Viceroy, Fulcanelli was determined to perfect an invention which would provide him with the key to eternal life. He was to name it... the Cronos device. 400 years later, one night in 1937, part of the vault in a building collapsed. Among the victims was a man of strange skin, the color of marble in moonlight. His chest mortally pierced, his last words... Suo tempore. This was the alchemist.