The 34-year-old star split from McIntosh last month amid allegations he had cheated on her with his ex-girlfriend Sarah Harper but the pair have now been spotted enjoying a cosy date in Los Angeles, where Brook is working on US sitcom 'One Big Happy', reported Daily Mirror.
"They are back on and giving things another go. They met up to talk and realised how much they'd missed each other," a source said.
The former couple are said to have enjoyed a romantic Italian meal before heading back to Brook's apartment in West Hollywood.