The News International-owned title launched the £3m campaign on Monday, posting the unbranded images at over 70 commuter stations across the capital, with the aim of making people question and think.
It also ran a series of half page ads in The Financial Times, The Independent, City AM, Metro, thelondonpaper and The Times.
Each of the six images appeared on a black background with no indication of the advertiser.
The images included Barack Obama standing in front of number 10 Downing Street, a golden football, a boy in swimming shorts, Winston Churchill alongside an out of focus David Cameron, a woman in a sports vest stretching and Cern's Large Hadron Collider.
From today all the sites will be reposted with the same images sitting behind the words 'The Times'.
However, the ads will not feature an end line and marks the first time in over 50 years that The Times has run a campaign without one.
Katie Vanneck, sales and marketing director of Times Media, said: "The Times is the only national daily without a dogma -- the paper does not tell you what to think but encourages the reader to question and to challenge.
"We wanted to reflect this ethos of 'show and not tell' in our brand campaign which is why we have gone for strong, simple images that set you questioning and thinking.
"We want readers to think again about our times and to think again about The Times.
"The same rationale was behind our decision to drop the end line. We want our readers to make up their own minds about what the paper means to them."
The posters did get commuters talking and writing comments on various websites.
Rick Lamb, search manager at Zed Media, questioned the ads on his personal blog site and drew several comments from readers who shared his curiosity.
One user wrote: "I've been walking past these adverts all week and they have been driving me mad. Who pays for all this advertising without disclosing their identity? Is that part of the gimmick?"
A separate user commented: "Ok, I Googled 'Obama' and London Underground and multitudes of other words yesterday, and nothing came up. I was thinking, 'is nobody else intrigued by this campaign?!?'
"So I am very glad to find that others are as curious as me. I even asked an attendant at Paddington what it was all about and he had no idea [the same images are on the barriers there]. Keep us posted if you find out anything!"
The campaign is set to run over the next six weeks. It was devised by CHI, Times Media's retained agency, and by the global brand consultants, venturethree. The media was bought by Mindshare.