His play Really Really[2] premiered at The Signature Theatre in Arlington, Virginia in January 2012,[3] breaking Signature Theatre box office records. A new production opened Off-Broadway at the Lucille Lortel Theater in January 2013 starring Zosia Mamet and Matt Lauria and directed by David Cromer, as part of MCC's 2012–2013 season. The MCC production was sold-out and twice extended. Colaizzo stepped into the play for three performances in the role of Johnson while actor Kobi Libii filmed a television pilot.[4]
In 2015, Colaizzo's medical drama LFE was picked up to pilot by CBS.[5] It starred Melissa Leo, Daniel Sharman, and Brandon Michael Hall. Later that year, Colaizzo inked a 2-year overall deal with CBS,[6] during which he served as an Executive Producer and co-writer for the pilot episode for the network's reboot of MacGyver.
In November 2017, it was announced Colaizzo would direct Brittany Runs a Marathon, starring Jillian Bell, from a screenplay he wrote, and would also serve as an executive producer.[7]