While in treatment, Gontier, sad and discouraged, began writing lyrics for songs regarding how he felt and what he went through in rehabilitation.Adam Gontier successfully completed treatment at CAMH; he and the band members felt that peace and tranquility would be required in order to record a successful second album. The band found just the place in Northern Ontario, in a cottage by themselves where they experimented, tested, and practiced songs. After three months at the cottage, they had about finished what would be on their second album. In the songs they would decide to include were lyrics that Gontier had scribbled in rehab. Adam had also posted lyrics to what was said to be a new song at the time. The first single from One-X, titled "Animal I Have Become", features lyrics Adam had written while getting sober. The second album contained at least four more songs which contain lyrics Adam wrote while in rehab, such as "Over and Over", "Gone Forever" and two more hit singles, "Pain" and "Never Too Late". In a 2006 interview, Gontier said that the album's material was more personal to him than the band's previous work because the material had come out of his experiences with despondence, drug abuse, and rehab that had constituted the past two years of his life.The album, titled One-X, was then released on June 13, 2006, and was guitarist Barry Stock's recorded debut.Adam Gontier has even done solo live performances at various rehabilitation centres as a "thank you" to the people who helped him get through his addiction. In these performances, he would play songs like "Pain", "Animal I Have Become" and "Never Too Late" to encourage and motivate other people under treatment to push forward and get over their addiction.
One-X was met with mostly positive reviews. The Toronto Star complimented the album with a review title of "One CD worth buying..." and focused on its lyrics, saying, "The lyrics really speak out to you, especially if you're going through a tough time in your life." Allmusic reviewer Corey Apar praised the music, saying it "remains catchy despite its lyrical darkness". The album did receive some negative criticism. Apar pointed out that Three Days Grace is "hardly innovative" in their approach to writing music and that "further distinctive qualities" would help the band separate itself "from their alt-metal peers".
One-X peaked at number two on the Canadian album chart and at number five on the Billboard 200,selling 78,000 copies in the US in its first week of release. Its first single, "Animal I Have Become", was Three Days Grace's most successful, becoming 2006's most played rock song in Canada and the album helped propel Three Days Grace to become the number one rock artist in airplay in the US and Canada in 2007, with Billboard ranking them as the number one rock artist of the year in 2007. One-X was certified platinum by the RIAA in the US on August 30, 2007, and double platinum by the CRIA in Canada in July 2007. Three Days Grace toured the US and Canada throughout the second half of 2006 and all of 2007 in support of One-X. In early 2008, they toured alongside Seether and Breaking Benjamin across the US.It was their first and only album under Sony BMG, the successor to the original Sony Music Entertainment & Bertelsmann Music Group. Two of the songs, "Animal I Have Become" and "Riot", off of the album were also featured in 2007's version of Smackdown vs Raw.
Life Starts Now (2009–2011)
From March to August 2008, to January to April 2009, Three Days Grace recorded their third album at The Warehouse Studio in Vancouver, British Columbia, and Los Angeles, with producer Howard Benson, who had worked with them on their previous releases.The album, entitled Life Starts Now, was released on September 22, 2009. Critics as well as band members have noted the album's departure from the angry tone of the band's previous releases into a lyrical style that comes off as more optimistic. According to guitarist Barry Stock, the album's theme centers around "a new sense of freshness" and the idea that "you don't have to be stuck in whatever it is you're dealing with. Whether it's good or bad, it's your choice to make a change.
Transit of Venus and Gontier's departure (2012–present)
On October 7, 2011, RCA Music Group announced it was disbanding Jive Records along with Arista Records and J Records. With the shutdown, the band (and all other artists previously signed to these three labels) will release their future material (including their upcoming fourth studio album) on the RCA Records brand.
On January 9, 2013, Three Days Grace announced that Adam Gontier was resigning from the band.Brad's brother, Matt Walst of My Darkest Days, would be touring with the band as lead vocals. They cited Adam Gontier's sudden departure due to medical reasons.
On January 16, 2013, it was reported that the band released details of Gontier's departure as being abrupt and unexplained.