Penguin is a 2020 Indian Tamil-language mystery thriller film written and directed by Eashvar Karthic in his directorial debut.

It stars Keerthy Suresh as a pregnant woman on the journey of solving the mystery of her first child's disappearance.

A sinister-looking stranger in a Charlie Chaplin mask holds a bloody bag while walking into a lake.

Rhythm, a young woman who resides in Kodaikanal, married to her husband Gautham, is seven months pregnant.

Raghu, Abi, Kathir, and Bhavana all try to console her and the police continue their search but Ajay cannot be found.

Back in the present, Rhythm is thinking about her happy times with Ajay, she sees an injured man being chased by a stranger in a Charlie Chaplin mask.

Rhythm still goes back to the lake, and on her way there, she sees a child run in front of her car.

Back in the present day, Raghu apologizes for his behavior and lets Ajay go home with Rhythm.

On the way to the therapist, Rhythm's dog Cyrus finds human remains in a dumpster.

[11] It was also marked as Keerthy's second female-centric film, after her performance in Mahanati (2018), which received critical acclaim.

[16][17] Karthik Palani assisted Tirru, before making his debut as the cinematographer in the film, he stated the preparation work took around three months, further adding that the fairly limited time allotted for shooting, did help in a cause, despite the unpredictable weather.

[18] He also experimented with camera angles which he stated that no recent Tamil film has had as many wide shots.

[21] Keerthy, in an interview with Scroll.in, described the film as "an emotional thriller, which is mostly about motherhood and the bond between mother and son.

"[22] Apart from Keerthy, the film features Linga and Madhampatty Rangaraj in pivotal roles in addition to several newcomers.

[24][25] Keerthy had experienced about the film's shooting in cold destinations such as Kodaikkanal, and also about the challenges faced during early starts and long days.

[27] Penguin's original soundtrack album features only one song composed by Santhosh Narayanan.

[27] Titled "Kolame", it was composed by Santhosh at his Future Tense Recording Studio located in Chennai, and he composed the songs and background score of the film, during the period of the COVID-19 lockdown in India,[28] after when the Tamil Nadu government granted permission for post-production works of the film.

[33][34] The soundtrack album features seven instrumental tracks, along with the song "Kolame" which was released by Sony Music South, on 10 August 2020.

[35] The album also features an additional track "Thaai" (only for the Tamil version), which had lyrics written by Vivek and sung by Anand Aravindakshan.

"[41] Shubra Gupta of The Indian Express gave the film 1.5 out of 5 stars stating "Keerthy Suresh tries to make the best of a bad job, and is quite a sight when squaring up to monsters, but the proceedings let her down.

"[42] M. Suganth of The Times of India gave the film 2.5 out of 5 stars stating "Eashvar Karthic provides us the answers in this emotional thriller that might be underwhelming compared to recent serial killer thrillers, but isn't a total letdown, especially for a first film.

Part of its success is due to the convincing performance of Keerthy Suresh, which brings out the vulnerability and the strength in this character.

"[3] Gauthaman Bhaskaran of the News18 gave 1.5 out of 5 stating "A thriller that loses its way not long after it begins to roll.

"[43] Nandini Ramanath of Scroll.in stated that "Eashvar Karthic's 132-minute film stumbles along on the strength of its visuals and Keerthy Suresh's suitably fraught performance.

[45] Baradwaj Rangan of Film Companion stated "Even the title has no motivation, unless you consider that the penguin is a bird that cannot fly.

"[46] In a positive note, Ranjani Krishnakumar of Firstpost gave 3 out of 5 stating "Penguin draws a clear line – this is a story about a mother.

"[47] Sowmya Rajendran of The News Minute gave 3.5 out of 5 stating "Penguin has its moments and Keerthy Suresh indeed makes the film very watchable.

But it is probably time to ask if this pressure to include 'twists' isn't killing a good story only because it seems too simple.

"[48] Haricharan Pudipeddi of Hindustan Times stated "Keerthy Suresh proves yet again she's an artist with a lot of potential.

If not for her commendable performance, the film would’ve struggled to make an impact with its convoluted writing.