CBS will air an unprecedented number of original programming hours this summer, on Tuesday revealing a sked that includes four dramas alongside the thrice-weekly reality staple “Big Brother.” The lineup includes three original hours of programming on Sunday.

Joining “Unforgettable” and the previously announced event series “Under the Dome” (pictured) and “Extant” on the scripted front is sultry legal drama “Reckless,” starring Anna Wood and Cam Gigandet.

The Eye will hold off on launching its summer fare until late June, with “Big Brother” kicking off its 16th season on Wednesday, June 25. This will mark the second straight year that the reality vet has launched in late June after traditionally starting its summer editions post-July 4.

“Big Brother” will be airing in the same timeslots as a year ago: Sunday and Wednesday at 8 p.m. and the live eviction show on Thursdays at 9.

As previously announced, “Under the Dome,” last summer’s top-rated program and the most-watched scripted summer skein in more than 20 years, returns for its sophomore season on Monday, June 30, and remains in the night’s 10 o’clock hour. The premiere episode will be written by Stephen King, on whose bestselling novel the series is based.

“Extant, a co-production of CBS Television Studios and Amblin Television, will have its premiere on Wednesday, July 9 — a week later than previously announced by CBS. The mystery thriller about a female astronaut (Halle Berry) trying to reconnect with her family when she returns after a year in outer space will follow “Big Brother” on Wednesdays.

Sundays get cooking on June 29 when “Big Brother” is followed by “Reckless” and “Unforgettable,” creating a three-hour block of original fare following “60 Minutes.”

“Reckless” is set in Charleston, S.C., where a gorgeous Yankee litigator and a charming southern attorney must hide their intense mutual attraction as a police sex scandal threatens to tear the city apart. Alongside Wood and Gigandet are Shawn Hatosy, Adam Rodriguez, Georgina Haig, Kim Wayans, Gregory Harrison and Michael Gladis. Dana Stevens, Kim Moses, Ian Sanders, Corey Miller and Catherine Hardwicke are executive producers for CBS Television Studios.