Robert De Niro's left hand:
Robert De Niro - who is said to be left handed (though he writes with his right hand) - has a 'complete' simian line in his left hand.
Actors who have a simian line can be expected to excell in performing 'intense' roles (find more 'famous simian line holders': HERE). The distal phalange of his left thumb appears to be relatively long (which is associated with a strong impulse to 'will'). The fingers of his left hand are 'balanced' and his left palm is 'square shaped'. Robert De Niro's personality has often been described as an 'introverted-person'; he is e.g. known for avoiding personal interviews.
• 2018 report with the Big Five personality profiles of 3 top-actors:
Robert De Niro, Jodie Foster & Anthony Hopkinds, all have a simian line!
Robert De Niro's right hand:
Robert De Niro appears to have a Sydney line (= extended head line) in his right hand. The distal phalange of his right thumb appears to be relatively long (which is associated with a strong impulse to 'will'). The fingers of his right hand are characterized by a long pinky finger + a relatively long ring finger resulting in (but his 2D:4D digit ratio looks normal (= pointer finger is slightly shorter than the long ring finger).
Robert De Niro is an American actor who is considered by many as the best (male) actor of all times - see: thebest100lists.com & toptenreviews.com.
Robert De Niro's world fame can be attributed to the diversity of his acting skills as seen in various movies like e.g.: 'The Godfather - part II' (1974), 'Taxi Driver' (1974), 'The Deer Hunter' (1980), 'Raging Bull' (1981), 'Awakenings' (1991), and 'The Good Shepherd' (2007).
'ROBERT DE NIRO'S HANDS'
Or, take a look at ...:
"The Godfather - part II" (official trailer)
"The Godfather - part II" (1974) received 6 acedemy awards, including: "... Best supporting actor: Robert De Niro...""Taxi Driver" (official trailer)
In "Taxi Driver" (1974) Robert De Niro won the 'best actor' award from the 'Los Angeles Film Critics Associations' (+ an Academy Award nomination for 'best actor').
"Awakenings" (official trailer)
In "Awakenings" (1991) Robert De Niro won the 'best actor' award from the 'National Board Review' (+ an Academy Award nomination for 'best actor').