The film, which has no dialogue, stars an ensemble cast that includes Prabhu Deva, Sananth, Remya Nambeesan, Indhuja Ravichandran, Deepak Paramesh, Shashank Purushotham, and Anish Padmanabhan.

The background music was composed by Santhosh Narayanan, cinematography was handled by Tirru, and the film was edited by Vivek Harshan.

[1] He said the absence of dialogue gave him more freedom to emphasise the film's other aspects, such as music, to increase its "thrill factor".

[3] Cinematography was handled by Tirru,[4] the film was edited by Vivek Harshan, and stunts were choreographed by the twin brothers Anbariv.

[5] Prabhu Deva called his role in Mercury unique and unusual compared with his previous films, where the script demanded a dance or comedy sequence.

[6] The other cast members Sananth, Deepak Paramesh, Indhuja Ravichandran, and Anish Padmanabhan had appeared in Karthik's earlier films.

[10] Because most of the filming was done indoors, Tirru chose not to keep the camera steady to avoid visual fatigue, either from the characters' points of view of that of a third person.

[12] Santhosh composed another promotional song called "Oru Mara Nizhalil", which was recorded by Sathyaprakash Dharmar and lyrics were written by Vivek.

"Oru Mara Nizhalil", which was was released on 19 April 2018, is a montage song that is picturised on the romance between the characters Michael (Sananth) and Meera (Indhuja).

[40] Anisha Javeri of IndieWire said, "Though the historical backdrop could have made for a compelling metaphor, the clichés and heavy-handedness of Mercury ultimately outweigh the novelty of its premise, while its sloppy social relevance angle does more to confound than clarify the disaster in question".

[41] Manoj Kumar R. of The Indian Express gave three-and-a-half stars out of five, stating: "Karthik Subbaraj's plot has a few gaps and he also uses the regular narrative techniques of the horror genre to create the moments of shock.

"[42] Sajin Srijith of The New Indian Express gave a rating of four out of five and said: "Karthik Subbaraj's Mercury is audacious, technically-impressive, and an experiment filled with delightful surprises".

[43] Nandini Ramnath of Scroll.in wrote: "Subbaraj tries to dress up a routine horror film with a social theme, but fortunately, the director has enough tricks up his sleeve to make the scary portions work".

[44] Arnab Bannerjee of Deccan Chronicle gave Mercury one-and-a-half five stars and stated: "Karthik Subbaraj tries to juggle a thriller horror story with a not-so-original twist".

[45] According to Baradwaj Rangan of Film Companion, Karthik made both a thriller and an "emotional horror-drama with a touch of eco-activism".