Condolences and remembrances from across the entertainment industry poured in after news broke Wednesday that Nichols had died suddenly at the age of 83.
"An inspiration and joy to know, a director who cried when he laughed, a friend without whom, well, we can't imagine our world, an indelible irreplaceable man," said Meryl Streep, who worked with Nichols on "Silkwood," "Heartburn" and the HBO adaptation of Tony Kushner's "Angels in America."
Over more than five decades, Nichols moved seamlessly between Broadway, television and movies, becoming one of the only people to win an Emmy, a Grammy, an Oscar and a Tony -- achieving "EGOT" status. His notable films include "Working Girl," "Primary Colors" and "The Birdcage," and he also oversaw stage hits such as "Spamalot," "Barefoot in the Park" and "The Odd Couple."
He was also a performer in his own right, as one half of the comedy duo Nichols and May with Elaine May.
Nathan Lane scored one of his biggest film hits playing a flamboyant drag queen in "The Birdcage." In a statement, Lane made mention of Nichols' own career in comedy.
"Along with Elaine May, Mike Nichols changed the face of comedy," said Lane. "He was an irreplaceable and loving genius who also changed my life."
Director Steven Spielberg hailed Nichols' versatility and personal virtues.
"This is a seismic loss," he said. "Mike was a friend, a muse, a mentor, one of America's all time greatest film and stage directors, and one of the most generous people I have ever known.
Like many Americans who came of age in the 1960s, "The Graduate" resonated profoundly for Spielberg.
"For me, 'The Graduate' was life altering -- both as an experience at the movies as well as a master class about how to stage a scene," he said. "Mike had a brilliant cinematic eye and uncanny hearing for keeping scenes ironic and real. Actors never gave him less than their personal best -- and then Mike would get from them even more. And in a room full of people, Mike was always the center of gravity."
Tom Hanks, who worked with Nichols on the political comedy "Charlie Wilson's War," evoked one of the director's credos in paying tribute to his late friend.
"Forward. We must always move forward. Otherwise what will become of us?" said Hanks. "Mike Nichols, who changed the lives of those who knew him, who loved him, who will miss him so."
Julia Roberts starred alongside Hanks in "Charlie Wilson's War" and also appeared in Nichols' "Closer." She said Nichols was a "most cherished friend" and a man who loved his wife, ABC News' Diane Sawyer, "utterly, immeasurably, magically."
"There are so few heroes in our world. So few impeccable craftsmen, so few people who personify unconditional love and friendship," said Roberts. "Mike Nichols was like no other. In every way he was remarkable and amazing. His musing were like pearls, his jokes were timeless and perfectly placed, his stories- detailed and wholly entertaining, his warm embrace was where you wanted to live forever. He savored life and friends and French macaroons. He always, always told the truth."
The accolades and achievements never went to his head, HBO CEO Richard Plepler said in a statement.
"Everyone overuses the word legend, particularly in our business," he said. "But Mike was in a class by himself. Brilliant, wise and a remarkable artist whose body of work for theater, film and television is simply unrivaled. But more importantly, he was also a consummate gentleman. The combination of all that talent and menschness won't be found again anytime soon."
Nichols successfully turned stage hits such as "Wit" and "Angels in America" into Emmy winning successes for HBO.
They were a perfect vehicle for a director who always made sure to return to Broadway despite his Hollywood achievements. One of those stage collaborators, Tom Stoppard, who worked with Nichols on "The Real Thing," said he was heartbroken over his friend's death.
"Everyone who was close to Mike has suffered a loss which cannot be repaired, ever," said Stoppard. "To have been his friend was a blessing. To have worked with him was both a privilege and the best of times. He was my hero."
John Goodman was directed by Mike Nichols in "What Planet Are You From?" and the Off-Broadway production of "The Seagull," said it was hard to imagine a world without Nichols.
"He made me feel as though I were a full partner or co-conspirator in finding clues to solve the puzzle; like a really slow Dr. Watson," said Goodman. "It's hard to imagine a world without him."
"Squid and the Whale" director Noah Baumbach said that Nichols was a frequent dining companion who was also source of personal support.
"Wes Anderson, Mike and I would have lunch and talk about what we loved: movies and plays and books and life and Mike said the smartest, truest things I've heard about all of them. His conversation was like poetry," said Baumbach. "One word or observation would say it all. And it was communicated with joy and tears. And during a particularly low point in my life, Mike offered comfort and hope in a way that actually made me feel better. Of course, he was also an all time great and I think about scenes from pretty much all of his movies on a regular basis. I wish he was here now to say the thing that made sense of his being gone."
For director Sam Mendes, Nichols was a genius who took time out to guide and share his insights with emerging artists.
"He was a giant," said Mendes. "But as many others like myself can testify, he also had a genius for friendship. He went out of his way to guide and mentor many young directors, who offered little in return except idolatry. I was one of those lucky enough to be counted amongst his friends. And - of course - he was my idol.
Scott Foundas and Cynthia Littleton contributed to this report.